資料no.f-7 · road maintenance manual for afghan government engineers 23 november 2005 ministry...

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資料 No.F-7

Road Maintenance Manual For Afghan Government Engineers

23 November 2005

Ministry of Public Works Islamic Republic of Afghanistan

Consultative Group – Transport Sector

Working Group 2 “Maintenance & Operation”

PRINTING FUNDED BY JICA

Road Maintenance Manual Ministry of Public Works / Islamic Republic of Afghanistan

Working Group 2 “Maintenance & Operation” / Consultative Group – Transport Sector

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MESSAGE This “Road Maintenance Manual for Afghan Government Engineers” is compiled by Working Group 2 “Maintenance & Operation” of Consultative Group – Transport Sector for Afghan government engineers to acquire the basic knowledge of road maintenance. Information contained here comes from various reports and recommendations produced by donors, who are also the members of Working Group 2. It is hoped that this manual will greatly help Afghan engineers to improve the road maintenance performance and maintain healthier road network in Afghanistan toward the future.

Wali Mohammad Rasooli Deputy Minister, MPW

Members of WG2, 23 November 2005



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Contents

Introduction 1 1. Road Improvement History in Afghanistan 2

1.1 Afghanistan as Important Section of Silk Road 2 1.2 Road Improvement in Modern History 3 1.3 History of Toll Roads in Afghanistan 5

2. Present Situation of Roads in Afghanistan 6

2.1 Road Classification and Length 6 2.2 Road Numbering System 8 2.3 Current Road Development Programs 10 2.4 Summary of Road Conditions 11 2.5 Road Maintenance Needs 13 2.6 Road Maintenance Costs 15

3. Objective and Types of Road Maintenance Operations 16

3.1 Objective of Road Maintenance 16 3.2 Types of Road Maintenance Operations 16

4. Maintenance of Different Road Types 18

4.1 General 18 4.2 Maintenance of Earth Roads 19 4.3 Maintenance of Gravel (Water Bound Macadam) Roads 20 4.4 Maintenance of Bituminous Surfaces 21 4.5 Special Repairs in Flexible Pavements 22 4.6 Maintenance of Cement Concrete Roads 24

5. Maintenance Inspection 26

5.1 Types of Maintenance Inspection 25 5.2 Inspection of Earthwork, Pavement and Shoulders 27 5.3 Inspection of Bridges 29 5.4 Inspection of Culverts 32 5.5 Inspection of Drainage and Protection Works 33 5.6 Inspection of Miscellaneous Works 34 5.7 Relevant Surveys 36



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6. Maintenance Methods 38

6.1 Routine Maintenance in General 38 6.2 Routine Maintenance of Gravel Roads 40 6.3 Routine Maintenance of Flexible Pavement 43 6.4 Routine Maintenance of Rigid Pavement 51 6.5 Routine Maintenance of Bridges and Culverts 53 6.6 Routine maintenance of Drainage and Protective Works 59 6.7 Routine Maintenance of Miscellaneous Works 62 6.8 Periodic Maintenance 64 6.9 Safety/Traffic Management during Maintenance 66

7. Appendix 69

7.1 Pavement Failure Mechanism 69 7.2 Winter Road Maintenance (Snow & Ice Control) 76 7.3 Maintenance Management System 90 7.4 Pictures of Typical Maintenance Machines 93 7.5 Glossary of Terms in Road Maintenance 104 7.6 Road Network in Afghanistan 2005 110

8. References Road Maintenance Technology Transfer 1999, Infrastructure Development

Institute – Japan Road Maintenance Manual for Republic of Kenya, JICA Photographic Presentation of Highway Maintenance 1996, Expressway

Technology Center of Japan Manual for Asphalt Pavement 1989, Japan Road Association Road Engineering 2001, Dr. Y. Makigami, Dr. T. Fukumoto, Dr. S. Ogino Road Maintenance Manual for Afghanistan, ADB Master Plan for Road Network Improvement Project 2005, ADB Highway Engineering 2004, Dr. S. K. Khanna, Dr. C.E. G. Justo Gravel Roads Maintenance and Design Manual, FHWA, Nov. 2000



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Introduction

Roads are lifeline to the Afghan development and their proper maintenance is critical to sustaining progress to be made. Donors have been assisting the Government of Islamic Republic Afghanistan to rehabilitate the road network in Afghanistan since end of the civil conflicts. Some Considerable segments sections of most important part of the National Road network have been completed and are already supporting economic recovery activities in this nation. Afghan side should respond to these donors’ efforts by planning and creating sources of funds for maintenance of those rehabilitated roads as soon as possible.

It was the importance of roads to development that made donors heavily invested over half billion dollars in reconstruction of this infrastructure as a top priority in standing the post-war Afghanistan economy. But, the Afghan economy will decline if its roads deteriorate. Therefore standing and funding a sound maintenance program is utterly important to progress in this country.

Quality roads warrant creation of a dedicated maintenance fund. Many developing countries learned this the hard way after they realized the negative impact of deteriorated roads to their poor economy. Once roads are neglected due to lack of funds, exponential costs will be needed for their rehabilitation. Several of these countries like India, Kazakhstan, Kyrgyz, Pakistan in neighboring regions and many others in the rest of the world have taken steps to create autonomous road authority and roads’ fund. Road user charges should be envisaged to go into a Road Fund.

Many countries worldwide are enjoying sound road network supported by a Road Fund, whereas there are a number of developing countries that are suffering deteriorating road network due to lack of funds. Once roads are neglected due to lack of funds, they will be ending up with needing exponential cost for rehabilitation. Road user charges, which include toll, fuel tax, car licenses, and custom duties, should be envisaged to go into a Road Fund.

Toll collection, which is the simplest and easiest among road user charges, must start soonest. Details of Toll Road Scheme for Afghanistan were discussed for the past five months by CG-TS WG3”Cost Recovery” that presented a proposal “Update and Final Report to CG-TS.” The new toll road scheme should be different from the old one that was reputed by fraud and swindle. Many developed countries have developed reliable toll systems. Once the new toll road scheme is decided, advanced toll collection technologies should be introduced to create a new toll road system. The World Bank has already offered such a technical assistance.

Many countries worldwide are enjoying the full private participation in toll road business and Afghanistan should look at the same direction. Privatizing just toll collection work as alone is the first step, and which should be followed by full privatization combining toll and O&M.



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1. Road Improvement History in Afghanistan 1.1 Afghanistan as Important Sections of Silk Roads Silk Route would usually go from Tehran, Herat, Bamiyan, to Kabul. The modern road cuts south at Herat to Farah, across Helmand River to Kandahar on it’s south bank, Ghazni, to Kabul. At Kabul the Silk Route heads NE over Hindu Kush Mountains. Another route goes to Pakistan and India over Khyber Pass, eventually ending in Delhi. From Kabul the route also heads NE into the Panjshir Valley, Kabul to Charikar [Bagram], and along the Panjshir River. It follows the narrow strip of Afghanistan, along the Oxus River to Sinkiang Province, China. The Silk Road may pose an impression that it is all one road. This is not really true. It consists of many sections, branches, and alternates. There were more than one end and several beginning points. Another misconception is that the road connects the important cities along the way. This is true when we build paved roads and highways in modern days. But in the days of the Silk Road, the object was to get from here to there by the quickest, safest, and most convenient paths. The existence of the road then made the cities great. The long land routes only lasted until transportation by sea became commonplace. By the 1st century of the current era, the land routes had heavy competition all over the ancient world. By the end of the 2nd century most of the famous routes were falling into disrepair, the trade having moved to the sea routes. Silk was only a minor article of trade carried on the route. Silk was the most exotic, but not the most common. The traders heading east to China carried gold and silver, precious stones, local textiles and carved ivory. This was used to pay for silk and porcelain, or spices like cinnamon bark. Pepper came in from India and joined the Silk Road in Afghanistan. And animals were also traded in both directions, the steppes of Iran and Afghanistan producing fine horses. The trade goods moved in fits and starts. Something picked up here and traded there, very little traveled the entire route. Silk traveled the entire road, as did pepper. That explains where the names came from.

Silk Road



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1.2 Road Improvement in Modern History Existing of formidable mountainous and desert ways in Afghanistan has given special features to road development history in Afghanistan. Afghanistan is divided by these areas from each other and there were only caravan ways, on which goods were transported. Series of Hindu Kush Mountains have imposed harsh traveling conditions and prevented Afghanistan from development of transportation and economical relation between each area. People lived remote from each other using camels and horses as means of transportation. The lack of good roads imposed high cost of even to go to bazaars in different regions. Road improvement in Afghanistan started to strengthen the transport connections with bordering countries. There were some railway projects and river harbors on the Amu Darya river waiting to be extended to major cities in the inland. In 1882 [1241], the railroad was opened from Peshawar to Lahor. In 1894 (1273), the construction of railway toward Chaman was finished. In 1885 (1264), the railway in the suburbs of Kaspin was extendd to Eshq Abad, and in 1888 (1267), up to Samarqand, in 1898 (1277) to Tashkand and Keshk. Between the years of 1913 to 1915 (1292-1294) the rail way of Bokhara to Termez was constructed, which passed from one of the most important trade center of Afghanistan M’Kkolfat. In 1957 (1335), the extention contract of Chaman Spin Boldak railway was signed. The Soviet Union has a vital role on solving of Afghanistan transportation problems and many roads were constructed with assistance from the Soviet Union. In 1954 (1333), Afghanistan received $210,000 for the construction the Kabul Avenues. In the first year of the five-year development plan between the years from 1957 to 1962 (1241- 1336) and in the year of 1959 (1338), the Soviet Union signed two new contracts of grants for construction of the highway between Keshk - Heart - Kandahar and the construction of Shindand Airport. In second year of the five year development plane between the years from 1962 to 1967 (1341 – 1342), the construction of roads became very active as indicated by the construction of the important path through the Hindu Kush mountains, which was to ensure the economic connection between Kabul and the northern provinces. Sever snow sliding and winds in mountainous areas caused delay in the work and such kind of events frequently happened which considerable mass part of mountain has fallen down and band roads. Winter in Salang areas continuous for nine months the permanent. Sever snowing has caused to form a mass level, which its thickness was from 5-6 meter. Constructional Engineers from Afghanistan and Soviet Union have proven their championship by passing of road through Hindu Kush Mountains in Salang pass. Salang pass which is called winter pass has constructed in a very crucial and complicated situation which has 3200 meter height, which has more than 2-5 km long length. Galleries have been constructed to protect road from snow sliding, sweeping of stone and sweeping of constructional materials. How ever this part of road which crosses from Winter Pass is called Salang pass and Salang tonal, of course Salang Pass is the Pass which locates beside Winter Pass, at the begging crossing of this path was planed by that way.



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In 1964 (1343), the construction work of this road was completed and opened in the presence of Afghan authorities and Soviet Union representative headed by (Agesk Kasigin) and has shortened the 200 km distance between Kabul and Pulekhomry. In 1965 (1344), the southern major cities, Keshk - Heart - Kandahar - Kabul were connected by highways. The Kabul -.Kandahar road is a part Asian Highways and connecting Turkey, Iran, Afghanistan, Pakistan, India, Burma, Laos, Thailand, and Vietnam together. In 1964 (1343), by the assistance of the Soviet Union, the construction work of Pulekhomry – Mazar Sharif Shoberghan road of 320km was began.These roads have been and will be remarkable economical and cultural importance for Afghanistan. As Afghanistan doesn’t have rail way and marine transpiration, paving of Kabul and Torkham road with 232Km in length, renewal of Kabul Kandahar Spin Boldak Road with 594 Km in length was done by the assistance of United States at the end of Afghanistan’s first five years development plan. In 1963 (1343), the reconstruction of Kandahar - Spin Boldak road was performed. And the reconstruction of Kabul - Kandahar road were in 1963 (1343) and the construction of Heart - Islam Qalah road with 121 km. These roads contributed greatly to trade with neighbor countries. At the beginning of 1979 (1358), the total length of Afghanistan roads was as long as 18500 km, which includes 7000km of paved roads and 8700 km of earth roads. These roads connected 24 province of Afghanistan but only half of these roads were serviceable throughout the year. The maintenance expenditure for roads was remarkably small because the number of cars was small and system of tax collection was defective.

Kandahar-Herat Road (Mar. 2005); Damaged but still under service



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1.3 History of Toll Roads in Afghanistan There is a history of toll collection in Afghanistan for road maintenance. The first of which is the toll system implemented in 1974. Tolls were collected by way of a system of toll stations scattered throughout the country and the revenue was accrued to the central revenue fund with no earmarking for road sector. The allocations to the road sector were by way of appropriations from the central revenue fund. A new system was implemented in 1999, which introduced earmarking the funds for construction and maintenance of highways, as stipulated in the regulation, “Regulations for Collecting Toll Fees”. Toll collection was organized by the MPW and the tolls were viewed as a source of revenue for the MPW. Through a decision by the High Council of Ministers on September 23, 2002, however, this road toll system was abolished. The reason is that in a number of locations, unauthorized toll collection stations had been established by private parties thereby creating hardships for travelers without contributing to the maintenance program. The study on revival of toll roads is currently under way by CG-TS WG3 “Cost Recovery” in light of urgent needs of establishing a road fund for maintenance works. However, the gap between the views of Ministry of Public Works and Ministry of Finance is too big to reach the immediate conclusions.

Kabul-Charikar Road, Aug.2005



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2. Present Situation of Roads in Afghanistan 2.1 Road Classification and Length The functional definitions of roads and highways in Afghanistan are derived from “Securing Afghanistan’s Future: Accomplishments and the Strategic Path Forward, TRANSPORT ANNEX, Technical Annex, January 2004”. On 26 December 2004, the Ministry of Public Works slightly modified these terms specifically: the term “Super Corridor” was renamed “Regional Highway”. Additionally, Type 1 and Type 2 Provincial Roads were consolidated to simply “Provincial Roads”. Roads are designed and built based on the technical definitions. The two most important factors in planning and selecting what type of road to construct or to what level to upgrade a current road are the projected average daily traffic (ADT) and the economic resources available. There is often a relationship between the technical definition of a road and its functional definition, but functional definitions are a tertiary factor in determining requirements for road construction or a road upgrade project. The “Master Plan for Road Improvement Project” has identified the lengths of each road type as shown in Table 2.1.

Table 2.1 Existing Road Network Classification and Length Road Classification Length, km Regional Highway 3,227 National Highway 4,906

Provincial Road 9,656 Rural Road (estimate) 17,000

Total 34,789 *Urban roads are excluded The functional definitions and technical definitions as defined by the “Interim Road and Highway Standards” are as shown in Table 2.2 and Table 2.3.

Table 2.2 Functional Definitions Road Type Functional Definition

Regional Highways

(formerly Super Corridors) are (planned) for two-lane expansion to make four lanes, fostering regional trade and economic linkages between Afghanistan and the neighboring countries, Iran, Pakistan, Tajikistan, Turkmenistan and Uzbekistan. Regional Highways are (will be) 4 lanes, dual 7-metre carriageway with medians.

National

Highways

promote trade and economic linkages and extend Regional Highways to provincial capitals contributing to peace, security, stability, economic growth and national integration

Provincial

Roads

improve the administrative, trade and economic contacts between district headquarters and respective provincial capitals and between important district headquarters

Rural Roads bring the hinterland in commercial contact with markets and seats of power



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Table 2.3 Technical Definitions Road type Technical Definition

Expressways-Type II are four or more (4+) lanes, paved roads. They have two or more lanes for each direction of traffic with a median separating the opposing lanes of traffic; lanes are 3.5 meters wide. Divided highways have access control (e.g. entrance and exit ramps) and are designed for higher speeds and can accommodate traffic in excess of 30,000 ADT

Expressways-Type I are four (4) lane paved roads with two lanes in each direction, lanes are 3.5 meters wide and the total roadway width is 24 meters. Exterior shoulders are three (3) meters wide and interior shoulders are two (2) meters wide including median barrier. Expressways are designed for higher speeds and can accommodate heavy traffic volume between 13,000 and 30,000 ADT

Major Roads are two lane paved roads with a seven (7) meter wide carriageway and 1.5 meter wide shoulders. Major Roads are designed for average traffic volume up to 13,000 ADT

Minor Roads are two lane gravel roads with a six (6) meter wide carriageway and 1.5 meter wide shoulders, where possible. Minor Roads have low average daily traffic of below 5,000 Passenger Car Units as Average Annual Daily Traffic (ADT) volume. Their surfaces are compacted gravel or a similar material

Non-Standard Roads are small roads and trails that are not significant enough to require engineering design or standardization. They typically have very low average daily traffic (ADT) and have gravel or dirt surfaces.

Cross Section of MAJOR ROAD from Interim Road and Highway Standards



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2.2 Road Numbering System There is no road numbering system at present in Afghanistan other than the road classification given above. The “Master Plan for Road Improvement Project” has adopted a road numbering system as follows:

Table 2.4 Road Numbering System Road Type Numbering system Regional

Highways have a prefix of RH and a 2 digit number representing the Regional Highway section starting from 01 to 99. Dividing the Ring Road into four sections between Kabul, Kandahar, Hirat and Mazare-Sharif and numbering them 01 to 04.

National Highways

have a prefix of NH and a 2-digit number representing the National Highway section starting from 01 to 99. At present there are fewer than 50 National Highway sections and so a 2-digit number will be used for the present. For example, the Bagrami – Jalalabad highway can be numbered as NH01. In order to give a regional orientation to numbering, National Highways are numbered according to the nearest major city. National Highways close to Kabul, Kandahar, Hirat and Mazar-e-Sherif are numbered 01 to 19, 20 to 29, 30 to 39 and 40 to 49 respectively.

Provincial Roads

have a prefix of PR and a 4-digit number representing the Provincial number code (2-digit geo-code) and 2 digits representing the ProvincialRoad section starting from 01 to 99. or example, the Aybak-Dara-I-Suf Provincial Road in Samangan can be numbered as PR1503 where 15 is the Provincial geocode for Samagan and 03 is the section from Aybak to Dara-I-Suf.

Rural Roads will have a prefix R and the Provincial number code and a 2-digit number again representing the Rural Road section starting from 01 to 99. For example, a Rural Road in Samangan can be numbered R1503 to distinguish it from Provincial Road 1503.

Table 2.5 Regional Highway Numbering

Highway No. Start End Length(km) RH01 Kabul Kandahar 483 RH02 Kandahar Hirat 564 RH03 Hirat Mazar e Sharif 747 RH04 Mazar e Sharif Kabul 407 RH05 Kabul Torkham 224 RH06 Kandahar Spin Boldak 104 RH07 Dilaram Zaranj 223 RH08 Hirat Islam Qala 124 RH09 Hirat Torghundi 119 RH10 Andkhoy Aqina 37 RH11 Naibabad Hayratan 57 RH12 Puli Khumri Sher Khan Bandar 138 (Total) 3227



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Table 2.6 National Highway Numbering Highway

No. Start End Length

(km) NH01 Jalalabad Asmar 130 NH02 Jalalabad Nuristan 67 NH03 Kabul Bagrami-Surobi-Gandumak-Jalalabad 175 NH04 Jabalussaraj Kohistan-Mahmud Raqi-Srobi 105 NH05 Chaharikar Bamyan-Yakawlang 248 NH06 Maidan Shar Chagcharan-Hirat 855 NH07 Hisa I Awali Bihsud Dushi 209 NH08 Kabul Pule Alam-Gardez-Khost-Gulam 297 NH09 Sayd Abad (RH01) Pule Alam-Khoshi 58 NH10 Ghazni Zumzt-Gardez 86 NH11 Ghazni Sharan-Zurmat 116 NH12 Matun Gurbuz 7 NH20 Kandahar Tirin Kot-Gizab-Daykundi-NH06 468 NH21 Ghirishk Khanishin 268 NH22 Dilaram Gard Holang 362 NH31 Dilaram Farah-Farah Rod 203 NH40 Shibirghan Chaghcharan 324 NH41 Panjab Mazar e Sharif 362 NH42 Khulm Kunduz 104 NH43 Kunduz Ishkashim 365 NH44 Taluqan Yangi Qala 97 Total 4906

Rehabilitation work on the road connecting Kandahar and Kandahar Airport (Mar. 2005)



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2.3 Current Road Development Program Afghanistan is receiving extensive assistance from the international donor community to reconstruct and further develop the road network. MPW is the primary implementing agency. The international donors funding road construction works include: USAID, Asian Development Bank, World Bank, United Nations, European Union, Islamic Development Bank, Japan, Kuwait, India, Iran, Italy, Pakistan, Saudi Arabia, Sweden

Other donors are providing technical assistance in the form of project feasibility studies, engineering design and construction supervision services and training. The current road development program as updated by the Consultative Group. 2.3.1 Regional Highways The focus of the road program is the reconstruction and completion of the ring road and principal road connections with neighboring countries (the regional highway network). Together the current or planned projects will complete the existing Regional Highways network to a two-lane paved road standard, with certain four-lane sections near Kabul and Kandahar. The next development stage will be the improvement of high-trafficked sections to a four-lane standard e.g. Kabul-Charikar. The master plan examines the need to improve other sections as traffic increases. 2.3.2 Other Roads

Other road programs are being carried out to reconstruct or improve National Highways, Provincial Roads and Rural Roads. NEEPRA, NRAP, and LIWP are reconstructing a large number of Provincial Roads and Rural Roads.

Kabul-Kandahar Road (Mar. 2005)

Labor Intensive Work Program for Jahgato, Wardak Province (2003)



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2.4 Summary of Road Conditions The overall condition of the road network surveyed by the “Master Plan for Road Improvement Project” is summarized in Figure 2.1 and Table 2.7. Pavement Length Pavement Conditions Road Width Terrain Conditions Figure 2.1 Road Conditions Figure 2.2 Traffic Volumes (2005)

0%

20%

40%

60%

80%

100%

NationalHighway

ProvincialRoads

Earth

Gravel

Bituminous

0%

20%

40%

60%

80%

100%

NationalHighway

ProvincialRoads

Mountain

Hilly

Rolling

Flat

0%

20%

40%

60%

80%

100%

NationalHighways

ProvincialRoads

w>10m

w=8-10m

w=6-8m

w<6m

0%

20%

40%

60%

80%

100%

National

Highways

Provincial

Roads

Bad

Poor

Fair

Good



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Table 2.7 Summary of Road Conditions Surveyed in 2005

Over 90% of PRs and NHs are either earth or gravel and there is often no clear distinction between the construction standard of a NH and PR.

The condition of the PRs surveyed was marginally better than the NHs surveyed

underlining this lack of distinction. It is possible the poorer condition of NHs is due to higher traffic.

The pavement condition rating is subjective and often influenced by spot defects. Many roads

are motorable along the greater part of their length but are impassable at specific locations such as rivers and sections where severe erosion or landslides have occurred.

Many gravel pavements have stood up extremely well despite a lack of maintenance over the

past 25 years and are motorable at speeds of 50km/h or higher on stretches.

Except for newly-constructed bridges, most bridges and culverts are in bad condition. Many are in danger of collapse from heavily-loaded vehicles or from being washed away. The loss of a single bridge can isolate large numbers of people.

A very large number of creeks and rivers have to be forded, and any rise in water level may

cut of the remainder of the road. There are very few low-level causeways or slipways which would alleviate this problem.

Many roads are impassable in winter due to snow, flooding and waterlogged pavements.

Areas are either cut off or forced to use long circuitous routes. The overall condition of the road network is much worse during winter.

75% to 80% of roads have a roadway with of <8 m. They could be rehabilitated or

reconstructed to the Low-Volume Road standard recommended elsewhere in the report with the little or no widening. However, improving such roads to a Minor Road standard with 9m roadway will involve significantly higher costs.

Many roads are unsafe by international standards. The mitigating factors are that traffic

volumes are generally low, travel speeds are low and vehicles do not drive at night. No accident information was obtained so it is not possible to gauge the extent of road accidents or deaths.

Old bridges on provincial roads; Mazar-e-sharif, Feb. 2005



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2.5 Road Maintenance Needs Roads are lifeline to the Afghan development and their proper maintenance is critical to sustaining progress to be made. Donors have been assisting the Government of Islamic Republic Afghanistan to rehabilitate the road network in Afghanistan since end of the civil conflicts. Some Considerable segments sections of most important part of the National Road network have been completed and are already supporting economic recovery activities in this nation.

It was the importance of roads to development that made donors heavily invested over half billion dollars in reconstruction of this infrastructure as a top priority in standing the post-war Afghanistan economy. But, the Afghan economy will decline if its roads deteriorate. Therefore standing and funding a sound maintenance program is utterly important to progress in this country.

Quality roads warrant creation of a dedicated maintenance fund. Many developing countries learned this the hard way after they realized the negative impact of deteriorated roads to their poor economy. Once roads are neglected due to lack of funds, exponential costs will be needed for their rehabilitation. 2.5.1 Strategy for Periodic Maintenance The strategy for routine and periodic maintenance should be to focus on those roads which are to be reconstructed or improved, or which are in fair-good condition where maintenance effort would not be wasted. The maintenance requirements of other roads will be addressed by special works described below. The proposed actions are:

Provide routine maintenance on roads only after completion of reconstruction or rehabilitation

Provide routine maintenance on roads in relatively good condition which will not be rehabilitated or improved until late in the master plan period

Provide routine maintenance on roads which have been re-opened following special works as described below

Do not provide routine maintenance on roads which are scheduled for reconstruction

Provide periodic maintenance on reconstructed/rehabilitated roads as required (assumed beginning approximately six years after completion).

The field surveys show that, although the great majority of National Highways and Provincial Roads are in poor or bad condition, most roads are motorable by 4WD vehicle and small or medium buses and trucks over the greater part of their length. But often they are blocked by water courses, landslides or badly failed pavement sections.

Dora Bamyan-Zarkharid Warak; July 2005, Master Plan



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These roads could be re-opened over their full length by initiating a program of spot repairs10 in advance of full reconstruction. Typical works required include:

Repair of landslides or landslips Temporary repair/replacement of dangerous bridges Construction of fords or causeways at river crossings Temporary restoration of badly failed pavement sections Drainage repairs

There are more than 4900 km or National Highway and 9600 km of Provincial Roads and the current and none of the projected road development program options will be able to reconstruct or improve all within 10 years. Therefore this option is extremely important for restoring a minimum level of mobility across the road network. We recommend MPW establish a special works program to address the needs of all National Highways and Provincial Roads which will not be selected for reconstruction until after 2010. A tentative estimate is that this will include approximately 2500 km of National Highway and 7500 km of Provincial Roads which will not be rehabilitated or reconstructed until after 2010. The program will gradually be reduced as (1) special works are completed and (2) roads are taken up for rehabilitation/reconstruction. The program would be funded from the recurrent budget. 2.5.2 Strategy for Winter Maintenance Afghanistan was faced with an exceptionally severe winter in 2005 which isolated many communities for weeks on end and showed the importance of winter maintenance. The Salang Pass was kept clear for all but a few days with funding assistance from the World Bank. MPW has drawn up a list of winter maintenance priorities. Category I roads require a high level of service because of their strategic importance in the road network. Category II roads have less priority and are not shown individually. In addition, there are other sections of National Highway and many Provincial Roads which require snow clearing as well.

Salang Pass (Feb. 2005)



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2.6 Road Maintenance Costs

Table 5.4 Maintenance Unit Cost Estimates, $/km/yr Road Class

Routine

Maintenance Periodic

Maintenance Total Provision for

Special Works Regional

Highway (paved) 3,000 5,500 8,500 NA

National

Highway (paved) 2,500 2,800 5,300 5,000

Provincial

Road(gravel) 1,000 2,000 3,000 2,000

Routine Maintenance Costs Routine maintenance costs for the master plan were estimated using World Bank and the Consultant’s sources in several countries. A reasonable level of service was assumed especially for gravel and earth roads which are subject to rapid deterioration. The cost estimates are direct costs, excluding MPW management and overheads, i.e. the cost of contracting routine maintenance. The resulting costs are similar to those estimated by the Transport Sector Review and contained in CG-TS Working Group 3’s presentation on Cost Recovery, 18 May 2005. Periodic Maintenance Costs Periodic maintenance costs were estimated using data from the World Bank ROCKS database (footnote 3) updated to 2005 princes and Paved Road Maintenance Needs (footnote 4). Regional Highways are assumed to receive a thin overlay at eight-year intervals ($44,000/km avg). National Highways receive a single bituminous surface treatment ($22,000/km) and Provincial Roads receive a re-gravelling ($17,000/km). Special Works Costs There are no guidelines for estimating an average unit cost for such works. Most of the works will involve minor bridges and drainage which the ROCKS database shows to be about 5% of total construction costs. Relating this to the average reconstruction costs for gravel Low-Volume and Minor Roads suggests average unit costs of $5,000/km and $2000/km for National Highways and Provincial Roads respectively. Winter Maintenance Costs Cost estimates for meeting this and other requirements on the remainder of the road network are not readily available. Canadian experience shows that snow clearing costs range from $250 to 1000/km/yr (US$) depending on the level of service provided. Main highways and arterial roads receive continuous snow clearance while secondary roads wait their turn and are cleared less frequently. There are additional costs for snow removal, ice control, abrasives, snow fencing etc. to be considered as well. Canadian winter maintenance requirements are among the highest in the world and unit costs are minimized through contracting and achieving economies of scale which may not be possible in Afghanistan.



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3. Objective and Types of Road Maintenance Operations 3.1 Objective of Road Maintenance The basic objective of maintenance is to be borne in mind while planning, inspection and execution of the same. The objective being, (i) to avoid/arrest deterioration of the pavement, and (ii) operate the highway system in such a way that the performance level of the road can be retained unaltered. In order to achieve the objective, a constant monitoring system of the performance is required to be put in place and accordingly the maintenance activities are planned. The planning should not only consider the safety, without causing any hindrance or disturbance to the traffic operations but should also be carried out efficiently, professionally and economically. 3.2 Types of Road Maintenance Operations The maintenance operations can be divided into 3 categories, viz, (i) Routine, (ii) Periodic and (iii) Emergency/Special. 3.2.1 Routine Maintenance This covers all types of maintenance activities and is carried out frequently to prevent any deterioration to the quality of roads. This type of maintenance is planned based on routine inspections of different components of the road comprising, (i) Road Works, (ii) Cross Drainage Works (Bridges, culverts and causeways), (iii) Drainage and Protection Works and (iv) Miscellaneous works.

Road Works:

Clearing of vegetation, rubbish and debris Restoring rain cuts and eroded portions of embankment slopes and other

earthwork activities Clearing of drifting sand in desert terrain, land slides in hilly terrain and snow

clearance in snowy areas Flexible pavement repairs for (i) pot holes, (ii) patching of local areas, (iii) crack

sealing, treatment of raveling, (iv) sand blotting of bleeding, (v) treatment of bitumen hungry areas and (vi) repairs to damaged edges

Rigid pavement repairs for, (i) joint maintenance, (ii) crack sealing, (iii) spot patching with Plain Cement Concrete, (iv) deep patching, (v) joint leveling, (vi) slab replacement, and (vii) other patch work

Shoulder maintenance

Cross Drainage Works: Repairs to cracks in concrete works in abutments, piers, wing walls and return

walls Repairs to approach slabs



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Expansion joint sealing Clearing the surface drainage system Repairs to parapet and railings

Drainage and Protection Works:

Lined and unlined drains Catch pits Chute drains Retaining walls Stone pitching

Miscellaneous Works:

Traffic signs Road marking and studs Km stones and other markers Safety/crash barriers and pedestrian guard rails Kerbs Toll Plaza building

3.2.2 Periodic Maintenance This covers all types of maintenance activities, which are carried out either at a pre-determined frequency or at a frequency judged by periodic inspection to restore the serviceability level. It covers the following types of maintenance activities: Road Works:

Application of functional overlay Application of structural overlay

Drainage and Protection Works:

Construction of new drains Construction of new protection works

3.2.3 Emergency and Special Maintenance This involves immediate repairs to roads affected by heavy rains, flooding, landslides, cyclonic damages, earthquake damages, sand dune formation, avalanches etc. For this type of maintenance either special contractor should be appointed or a dedicated force be part of the maintenance wing of the MPW.



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4. Maintenance of Different Road Types 4.1 General After knowing the various defects that may cause pavement failure, it is necessary to study the different measures that are adopted to maintain and upkeep the pavement for their excellent functions. As a basic principle, it may be observed that a highway which is designed based on scientific standing would resist the various detrimental forces and would need the minimum maintenance. Various maintenance operations are:

Routine or periodic maintenance Special repairs Resurfacing

Routine or periodic maintenance is one that may be needed for any type of road whether it is designed and constructed with scientific bias or not. Since the highways are exposed to the moving traffic and adverse climatic conditions, they would positively wear out. Even if the highways are not used circumstantially, it may be stated that they also would need maintenance for their upkeep, as the factors that cause damage to the pavements are more than one. Traffic is one of the many factors. The longitudinal and cross drains would need attention under the routine maintenance work. One of the common items of maintenance work is the removal of slit, rubbish and weeds from the longitudinal and cross drains. When the pavement surface is severely damaged or after the useful service life, it may be necessary to renew the surface or provide a surface dressing. Following is a brief list of various routine and or periodic maintenance works for highways:

Upkeep of carriageway Maintenance of shoulders and sub-grade Maintenance of side drains and other ancillary works Improvement of highway geometric and traffic controls

The responsibility of planning, designing and constructing of new networks is obviously assigned to each section geographically and the maintenance also thus is assigned to the same groups of sections. The engineers thus would maintain the complete records of each case commencing from its design and construction stages. Unless such records are available at hand, it would be difficult to assess the real cause of the problems. The maintenance schedule listed above of routine typed and the repairs are carried out at regular interval like (i) day to day, and (ii) seasonal. The maintenance techniques are now discussed for different type of highways.



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4.2 Maintenance of Earth Roads The usual damages caused in the earth roads needing frequent maintenance are:

formation of dust in dry weather formation of longitudinal ruts along wheel path of vehicles. formation of cross ruts along the surface after monsoons due to surface water

The dust nuisance may be remedied by the following methods:

Frequent sprinkling of water Treatment with calcium chloride Use of other dust palliatives

Application of calcium chloride retains some water due to the hygroscopic nature of the mix. Oiled earth roads are also common these days. Periodical maintenance by spreading moist soil along the ruts and reshaping of the camber is necessary. Formation of cross ruts may be due to excessive cross slope. However in areas of heavy rain fall, it may not be possible to avoid these in untreated earth road. Hence either these ruts should be repaired from time to time during and after the monsoons or a surface treatment or stabilized layer be provided on the top.

Paktya, June 2005, Master Plan



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4.3 Maintenance of Gravel (Water Bound Macadam) Roads Gravel roads are considered superior to earth roads as they can carry heavier traffic. A well compacted crushed rock or gravel road is fairy resilient and does not become slippery when wet. When crushed stones are used as the material, it is often called Water Bound Macadam (WBM). The shape of crushed stones produces interlocking and binding action is achieved by sand and stone dust as filler in presence of water. WBM roads are damaged rapidly due to heavy mixed traffic and adverse climatic conditions. In dry weather dust is formed and during rains mud is formed. The steel tired bullock carts cause severe wear and tear to the WBM surface. The fast moving automobiles raise dust in dry weather and churn-up mud in wet conditions. Due to the combined effects of traffic and the rain water washing away the soil binder for the surface, the stone aggregates protrude out or get loose on the surface, layer. Pot holes and ruts are also formed in localized spots of WBM roads. To prevent the aggregate from getting loosened from the surface course, it is necessary to replace the soil binder periodically. This is done by spreading a thin layer of moist soil binder of the surface as a part of periodic maintenance, particularly after the monsoons. Dust nuisance can be effectively prevented by providing bituminous surface dressing course over WBM pavement. However temporary measures include spraying of dust palliatives. Pot holes and ruts formed should be patched up. The patch repair work is carried out by first cutting out a rectangular shape of the defective area to remove the stones up to the affected depth. Then with coarse aggregates of the same size (using part of the old aggregate and remaining fresh aggregate) the patch is filled up and compacted well by ramming such that the patched area is about 1 cm above the general pavement surface. This allows for the further compaction of this patched portion, under traffic. Wet soil binder is applied on the surface of the patched area to fill up the interstices and the surface is rammed again. After the period to useful life of the WBM road or when the layer fails extensively, a resurfacing is called for. If the thickness requirement of the old road was inadequate, the thickness of the WBM pavement is increased during the resurfacing.

Road maintenance machines; Kandahar, Mar.2005



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4.4 Maintenance of Bituminous Surfaces Mainly the maintenance works of bituminous surfacing consist of: Patch repairs, Pot holes and repairs, Surface treatments, Resurfacing. 4.4.1 Patch Repairs Patch repairs are carried out on the damaged or improper road surface. Localized depression cause pot hole formations in the surface layers. Inadequate or defective binding material causes removal of aggregates during monsoons. Patching may be done on affected localized areas of sections using a cold premix. 4.4.2 Pot Holes and Repairs Pot hole are cut to rectangular shape and the affected materials is the section is removed until the sound materials are encountered. The excavated holes are cleaned and applied with primers. A premixed material is then placed in the sections. Generally, cutback or emulsion is used as binder. The material so placed in the pot hole, is well compacted by ramming to avoid any raveling. The materials in pot holes are placed in thickness of 6cm or so. It is however necessary to replace the base course materials with similar new material if the failure has been detected in the base course layer. The finished level of the patches is kept slightly above original level to allow for subsequent compaction under traffic. 4.4.3 Surface Treatment Excess of bitumen in the surface materials bleeds and the pavement becomes patchy and slippery. Corrugations or rutting or shoving develop in such pavement surfaces. It is customary to spread blotting material such as aggregate chips of maximum size of about 10 mm of coarse sand during summer. Necessary rolling is done to develop permanent bond between the existing surface and the new materials, after heating the surface if necessary. The binders in the black top surfaces also get oxidized due to aging. This develops minute cracking in the pavement surface. Such pavement surfaces are applied with a renewal coat or seal coat. If the surface has been seriously damaged due to oxidization or volatilization of binder materials, it may be necessary to apply more than one layer of surface treatments. 4.4.4 Resurfacing In the event when the pavement surface is totally worn out and develops a poor riding surface, it may be more economical to provide an additional surface course on the existing surface.



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4.5 Special Repairs in Flexible Pavements 4.5.1 Wave and Corrugation (1) The factors which contribute to formation of waves and corrugations Defecting rolling If the rolling during construction stage is improper thus leaving the formation of waves then the process being progressive, the wave formation would continue indefinitely. However the subsequent traffic operations would also cause similar effects if the rolling is inadequate during the construction stage. Poor subgrade conditions Subgrade consisting of poor soils including highly plastic or organic soils and high water table close to subgrade surface may cause non uniform and inadequate subgrade stability. When boulders are used as soling course in such subgrades there is differential settlement of sinking of these stones. All these would contribute to formation of corrugated pavement surface. Poor gradation or mix Defective gradation or mix for the surface layer is another factor which gives rise to the wave formation. Pushing and pulling caused due to the vehicular movement enhance the defect further more. Compaction temperature Viscous state of the bitumen binder greatly depends upon the temperature and thus very high temperature during mixing and compaction (rolling) of bituminous mix would make the resulting pavement surface layer with low stability. Unstable underlying layers Weak underlying layers also cause the formation of waves due to repeated plying to vehicles on such road. Failure of any one of the pavement layers can cause surface deformations. (2) Remedial Measures There appears to be no way to improve the road surface once the waves and corrugation are already formed. Usually another layer of surface course is laid after laying a leveling course. But often the waves and corrugation again develop, unless the basic reason for this problem is investigated and proper remedial measure is taken. If the instability of underlying layer is due to excessive moisture conditions, suitable subsurface drainage system is warranted to remedy the defect permanently. If the failure is due to improper compaction of the lower layers, this would need complete reconstruction. Depending upon the failure of a given layer, the pavements would be reconstructed right from the defective stage. Since the above factors would be carefully observed in



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replacement of layers, the pavement section so constructed may offer satisfactory riding quality. 4.5.2 Skidding of Pavement Surfaces Skid resistance of property of pavement surfaces is essential requirement of highway safety. The skid resistance or the friction of the pavement surface may be measured using any one of the devices such as the pendulum type friction recorder of the skid testing device attached to test vehicle or the instrument mounted dynamic skid resistance tester towed by another vehicle. Skidding has been contributing to the large number of accidents on highways. Statistics show that about 40 percent of the accidents are due to the poor skid resistance offered by the pavement surface. It may not be possible to construct highways which would completely eliminate skidding of the vehicles. Investigation carried out on this aspect indicates that the sufficient degree of skid resistance can be built into the road surfaces and can be maintained through proper construction and maintenance controls. Water, clay, dust, dry sand, oil and grease on the pavements are few factors which cause skidding. These materials in the pavement surfaces check a good grip between tire and the pavement surface. Skidding is of three types. (a) Straight skidding (b) impending skidding (c) sideway skidding. The straight skidding occurs in the direction of travel when the sudden brakes are applied. Impending skidding is encountered when the skidding occurs on curves where sufficient super elevation is not provided or when the coefficient of friction in inadequate. Highways can develop sufficient skid resistance if they are maintained clean and dry. But the presence of water film, debris and polishing characteristics of aggregate influence the skid resistance property. Rough surfaces or textures like those of gravel road; WBM and cement concrete roads offer sufficient amount of skid resistance. Bituminous pavements are more prone to skidding. Wheels do the polishing of the aggregates and excessive bitumen bleeding to the surface produces a smooth skid-prone surface. The remedial measure mainly is renewal of the wearing surface. Sometimes in case of bituminous surfacing, the chippings are spread over them after heating the surface and rolled to form a non-skid riding surface.



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4.6 Maintenance of Cement Concrete Roads It may be stated here that very little maintenance is needed for cement concrete roads if they are well designed and constructed. Main defect in this type of road is formation of cracks. It is therefore necessary to examine the cracks and causes are ascertained before any remedial measure is adopted. 4.6.1 Treatment of Cracks The cracks developed in cement concrete (CC) may be classified into two groups: Temperature cracks Which are initially fine cracks or hair-cracks formed across the slab, in between a pair of transverse of longitudinal joints, dividing the slab length into two or more approximately equal parts due to the temperature stresses like the shrinkage stress, warping stress, etc, in the slab. Structural cracks Formed near the edge and corner regions of the slab, due to combined wheel load and warping stresses in the slab. The presence of fine cracks only as such are not harmful and do not call for immediate maintenance. As the cracks due to the shrinkage in the CG pavement start from the bottom of the slab, the cracks at the bottom portion would have got widened. Due to repeated application of heavy wheel loads and the variations in temperature and moisture conditions, the cracks get widened and further deterioration becomes rapid. Once the surface water starts getting into the pavement and the subgrade through the widened cracks, progressive failure or the pavement is imminent. Therefore before these cracks get wide enough to permit infiltration of water, they should be sealed off to prevent rapid deterioration. The dirt, sand and other loose particles at the cracks are thoroughly cleaned using a sharp tool, stiff brush and a pressure blower. Kerosene oil is applied on the cleaned cracks to facilitate proper bonding of the sealing material. The cracks are then filled by suitable grade bituminous sealing compound, heated to liquid consistency. The sealer is placed up to about 3 mm above the level of the slab along the cracks and layer of sand is spread over it to protect the sealer temporarily. The formation of structural cracks in CG slabs should be viewed seriously and needs immediate attention, as these indicate possible beginning of pavement failure. First the cause of the failure should be investigated. If the failure is confined to one or a few slab only at a particular location, and in general there are no structural cracks in other slab, the failure may be localized one due to some weak spot in the sub-grade or due to localized settlement of embankment or underground drainage problem. The maintenance work in such a case involves first remedy of the basic cause of the failure of the pavement, immediate steps are to be taken to expeditiously before the structural cracks develop in other slabs also. It is not worth while to provide an overly over a badly cracked or failed CG pavement as the riding surface becomes very unsatisfactory due to uneven



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settlement of the cracked and broken slabs. In such a case the only permanent solution is removal of the broken-up CG pavement slabs and re-construction of new flexible or rigid pavement. 4.6.2 Maintenance of Joints Joints are the weakest parts in CG pavements. The efficiency of the pavement is determined by the proper functioning of the joints. Majority of the failure in the CG pavements are observed at or near the joints. Therefore utmost care is to be taken to see that the filler and sealer materials are intact at the joints. During summer the joint sealer materials is squeezed out of the expansion joints due to the expansion of the slabs; subsequently as the slabs contract during winter, the joint gap opens out and cracks are formed in the old sealer material. Therefore periodic maintenance of the joint sealer is essential both at expansion and contraction joints as part of routine maintenance work of the CG pavement. The opened-up joints are cleaned with brush and refilled with suitable joint sealer material before the start of the rains. The joint filler material at the expansion joints may get damaged or deteriorated after several years of pavement life. The repair consists of removal of deteriorated filler and dealer materials from the expansion joints cleaning up replacement with new filler board (provided with suitable grooves cut on the bottom half at the positions of the dowel bars) and sealing the top of the joints with suitable sealer material. It will be convenient to insert the new filler board at the expansion joints during winter season when the joint opening is widest.

Kandahar-Heart road, Mar. 2005



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5. Maintenance Inspection 5.1 Types of Maintenance Inspection

Aim of the maintenance inspection is to evaluate the conditions, defects and deficiencies and distress manifestation of the road and its components like bridges, culverts, causeways and other structures besides road signs and other road furniture. The site data is collected on regular/emergency basis and applied for appropriate maintenance measures. There are three categories of inspection,(1)Routine, (2)Periodic, (3)Emergency/Special. 5.1.1 Routine Inspection It is carried out once or twice a year. In this, obvious visual deficiencies are to be noted. The deficiencies if not attended to promptly will lead to accidents or cause high maintenance and repair costs. Generally the items covered in the visual inspection are:

Earthwork, pavement and shoulders Bridges Culverts and causeways Drainage and protection works Road furniture Miscellaneous items.

5.1.2 Periodic Inspection This is carried out at intervals as specified in the respective items. It involves more intensive and detailed examination of various elements. It will be either data collection by actual survey or close visual assessment supplemented by standard instrumental aids for:

Traffic census Road roughness survey Axle load survey Benkelman Beam deflection test.

Emergency/Special Inspection: This is undertaken in the event of unusual occurrences such as accidents, passage of unusually heavy loads, severe earthquakes, heavy rains, flooding, cyclones, landslides, sand dunes formation, major weaknesses or deficiencies noticed during routine inspections. Emergency/special inspection requires considerable supplementary testing and also may require redesign.



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5.2 Inspection of Earthwork, Pavement and Shoulders A careful inspection of the road needs to be made to collect information about the earthwork, pavement and shoulders comprising details of cracking, rutting, potholes, raveling, edge breaking, embankment failure, land slide and shoulder failure. For rigid pavements the information to be collected should include, (i) longitudinal, transverse and construction joints, (ii) pop-outs, (iii) potholes and (iv) broken corners. The condition surveys will be planned and programmed by the Chief Maintenance Engineer (CME) of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of inspectors and field assistants will collect data and will be responsible for the surveys, data collection and analysis. Visual inspection should be carried out preferably twice a year, before and after rains or during the snow season and melting of snow as per the terrain. Simple tools like, (i) 3-metre tape, (ii) 30-metre tape, (iii) 3-metre straight edge with wedge and (iv) crack gauge will be required for making the needed measurements. For the purpose of inspection, the road should be divided into kilometer wise sections and the data collected at every 100 meters. The inspection is carried out by walking along the road with frequent stops to examine and record the damages. The data should be collected and assessed on the following features:

Mazar-e-sharif, Feb. 2005



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Table 5.1 Inspection of Earthwork, Flexible Pavement, and Rigid Pavement

Type of Distress Symptoms Recording Parameters Earthwork Embankment Damage

Erosion, rain cuts, slope failure Extent of damage along the road length

Landslide

Slope failure

Extent of damage along the road length

Flexible Pavement Cracking --Hairline crack --Alligator crack --Longitudinal crack --Edge cracks --Shrinkage crack --Reflection crack

--Short and fine cracks at close intervals on the surface --Inter-connected cracks forming a series of small blocks --Cracks in a straight line along the road --Crack near and parallel to pavement edge --Cracks in transverse direction or inter-connected cracks forming a series of large blocks --Sympathetic cracks over joints and cracks in the pavement underneath

Areas of cracking and their average width

Rutting Longitudinal depression in the wheel tracks

Depth of rutting

Pothole Appearance of bowl shaped holes, usually after rains

Number of potholes with dimensions

Ravelling Failure of binder to hold the aggregate shown up by pockmarks or eroded areas on surface

Area affected

Smooth surface Slippery

Area affected

Bleeding Collection of binder on the surface

Area affected

Hungry Loss of aggregates

Area affected

Edge breaking Irregular breaking of pavement edges

Length affected

Rigid Pavement Crack Concrete surface Area affected Joint Longitudinal, transversal Area affected Pop-out Joint, broken area Area affected Broken corner Edge cracking Area affected Shoulder Shoulder condition Loss of material, depression, slope Extent of damage



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5.3 Inspection of Bridges A careful inspection should be made to collect the information on the condition of bridges along the road (different types of bridges should be inventoried for each road). The condition surveys will be planned and programmed by the CME of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of inspectors and field assistants will collect data and will be responsible for the surveys, data collection and analysis. Visual inspection should be carried out preferably twice a year, before and after rains or during the snow season and melting of snow as per the terrain. Simple tools like, (i) 3-metre tape, (ii) 30-metre tape, (iii) 3-metre straight edge with wedge and (iv) crack gauge will be required for making the needed measurements. Inspection should be carried out for all the bridges along the road and the important items to be checked/considered are in the subsequent paragraphs. 5.3.1 Debris, Dirt and Vegetation Bridges should always be checked against debris, dirt and vegetation growth as these blocks the waterway and result in damaging the bridge. Deck Drainage System

Water flowing out of the drainage spouts should be deflected away from falling directly on supporting main girders or cross girders

Inadequate cross slope or non-functioning drainage outflow system on riding surface to be identified

Spouts to be checked for deterioration, damage and blockage Projection of spouts inside of structure also to be checked Projection of spouts inside of structure also to be checked so that structural

members are not damaged Railing/Parapet/Crash Barrier Damages due to corrosion and damages due to impacts of errant vehicles, cracks, spalling, sealing etc in concrete or any missing parts Footpath slabs and Kerbs While footpaths shall be inspected for cracks, spalling, sealing or potholes, the kerbs

Wooden Bridge in Nuristan; June 2005, Master Plan



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shall be inspected for condition of joints and damages if any due to accidents. Any missing footpath slabs shall be recorded. Bearings

Positioning of bearings Damages to pedestals Debris and vegetation accumulation under bearing Cleanliness of the area around bearings Splitting, tearing or cracking of elastomer in case of Elastomeric bearings Fallen cut segmental rollers, corrosion, lubrication system, damages to pins,

knuckles and sliding or rolling surfaces and cracks and bends in metal parts Expansion Joint For the inspection of expansion joints the following points should be taken care of:

Corrosion to metal parts of the joints Loose or damaged fixtures and fastening (bolts and steel parts) Debris or vegetation in the joints-stones or other debris can stop some of the parts

from moving Damage to the concrete of the superstructure or of the dirt wall Damages to rubber water seals, which prevents water and debris to get into the

joint Fingers of the finger type expansion joints may deform.

Wearing Course Deterioration of wearing course affects ride ability and can lead to distress in the structural deck slab and main supporting members from water leaking into deck through cracks, potholes, depressions or disintegration of road surfacing. Road Surface at Approach Slab and Pavement Interface The interface of approach slab and flexible pavement to be checked against depression or differential settlement to provide a smooth riding quality Slope Protection Displacement of stones, erosion of slopes, undue scours at toe of pitching. Bed Protection Settling of bed, any washed away material. River Training Rivers can change their course either slowly or suddenly which after certain period can damage a bridge. To prevent a river from changing its course near the bridge, river training works are provided. The inspection of these river training works is to be made periodically to report about:

Any abnormal change in the flow pattern both on the upstream and downstream of the bridge (should be provided with sketches).

Any obstructions in the waterway like presence of undergrowth blocking a span or projection of the hard bank deflecting the stream resulting in only part of the waterway being effective.

Adequacy of the waterway.



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Maximum high flood level (HFL), scour values, afflux etc. Substructure and Retaining Walls Substructure comprises abutment, return walls, wing walls, and piers.

For concrete the inspection shall cover crack, spalling of concrete and corrosion of reinforcement.

For stone and brick masonry works inspection to cover cracking, bulging and pointing.

Superstructure Each span of the bridge should be checked from the top of the deck as well as from under the deck pertaining to:

Impact damages to beams, trusses or bracings caused by vehicles Debris and vegetation accumulation on beams, trusses, bracings or in the joints. Any sign of wetness due to overflowing of water through the bridge deck Excessive deflection in superstructure Cracking and spalling in concrete works Corrosion in reinforcement

Foundation The foundations being below the bed level shall be inspected during high flood to ascertain the adequacy. To find the maximum depth of scour, soundings at regular intervals have to be taken. After the flood, general condition of the foundation has to be inspected and aspects like cracking, disintegration, decay, erosion, cavitations, damage due to impact of floating bodies in the river etc. has to be checked.

90km point from Mazar-e-sharif to Kabul, 2004 Scouring of footing is observed



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5.4 Inspection of Culverts A careful inspection shall be made to collect the information on the condition of culverts along the road. The condition surveys will be planned and programmed by the CME of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of inspectors and field assistants will collect data and will be responsible for the surveys, data collection and analysis. Inspection should be carried out preferably twice a year, preferably one during the rainy season and the other soon after rains or during the snow season and melting of snow as per the terrain. Simple tools like, (i) 3-metre tape, and (ii) 30-metre tape will be required for making the needed measurements. Inspection shall be carried out from culvert to culvert along the road and following points be recorded:

Debris, vegetation etc. inside or near the culvert Silting on the channel Settlement of parts of the culvert Scour at ends of culverts and edges of aprons

While concrete works in culverts will be inspected for cracking, spalling and corrosion of reinforcement, stone and masonry works shall be inspected for cracking, bulging and pointing.

Covering the riverbed with cement concrete adjacent to a pipe culvert



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5.5 Inspection of Drainage and Protection Works A careful inspection shall be made to collect the information on the condition of drainage and protection works along the road. The condition surveys will be planned and programmed by the CME of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of inspectors and field assistants will collect data and will be responsible for the surveys, data collection and analysis. Inspection should be carried out preferably twice a year, preferably one during the rainy season and the other soon after rains or during the snow season and melting of snow as per the terrain. Simple tools like, (i) 3-metre tape, and (ii) 30-metre tape will be required for making the needed measurements. For the purpose of inspection, the road should be divided into kilometer wise sections and the data collected at every 100 meters. Walking along the road with frequent stops to examine and record the damages carries out the inspection. While concrete works in all drainage and protection works will be inspected for cracking, spalling and corrosion of reinforcement, stone and masonry works shall be inspected for cracking, bulging and pointing. Apart from the above inspections, drains and protection works having following defects will be covered under this inspection. Lined and Unlined Drains

Obstruction of drain due to vegetation growth, bushes, fallen trees, debris, loose silt or rock

Silting due to flat slope of drain Ponding of drain due to blockage or too flat gradient Damaged/destroyed drain cross-section due to vehicular traffic or caving in Damage of drain lining due to settlement, erosion of soil under it Erosion at drain outfall due to too concentrated or fast flow

Catch pits Sump deposition in the catch pits Loss of cover Chocking of inlet/outlet pipe

Chute Drains Drain obstruction due to vegetation growth, bushes, fallen trees, debris, loose silt

or rock Damaged/destroyed drain cross-section Erosion of soil at out-fall Damage of cut-off wall in form of broken portion Gap in stone flooring or missing stone

Retaining Wall Chocking of weep holes

Stone Pitching Loss of stones Erosion of soil below pitching Increase of void size between stones



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5.6 Inspection of Miscellaneous Works A careful inspection shall be made to collect the information on the condition of miscellaneous items along the road viz. traffic signs, road markings and studs, distance measure stones and culvert/bridge marker posts, safety barriers and pedestrian guard rail, toll plaza buildings. The condition surveys will be planned and programmed by the CME of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of inspectors and field assistants will collect data and will be responsible for the surveys, data collection and analysis. Inspection should be carried out preferably twice a year, preferably one during the rainy season and the other soon after rains or during the snow season and melting of snow as per the terrain. Simple tools like, (i) 3-metre tape, and (ii) 30-metre tape will be required for making the needed measurements. For the purpose of inspection, the road should be divided into kilometer wise sections and the data collected at every 100 meters. Walking along the road with frequent stops to examine and record the damages carries out the inspection. While concrete works in all miscellaneous items will be inspected for cracking, spalling and corrosion of reinforcement, stone and masonry works shall be inspected for cracking, bulging and pointing. The above-mentioned miscellaneous items having following defects will be covered under this inspection:

Traffic Signs

Missing signs Weathered sign information Bent sign supports Weathered paint on gantry and

support posts Missing nuts and bolts Any traffic sign no longer needed

(e.g. after completion of maintenance works etc.)

Road Markings and Studs Length of weathered portion of road marking Weathered arrow markings etc. Missing road studs

Distance Measure Stones and Culvert/Bridge Marker Posts

Missing distance measure stones (e.g. 200m Stones, Km Stones, 5th. Km Stones)/marker posts

Traffic Sign in Kabul, Nov 2005



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Weathered paint/information on stones/marker posts Damaged stone due to accident Growth of vegetation hiding the stones/marker posts

Safety Barriers and Pedestrian Guard Rail

Missing safety barriers and pedestrian guard rails Weathered paint on safety barriers and pedestrian guard rails Missing nuts and bolts from the safety barriers and pedestrian guard rails Growth of vegetation in front of safety barriers and pedestrian guard rails Corrosion of any portion of safety barriers and pedestrian guard rails

Kerbs

Missing kerbs Weathered paint on kerbs Damaged kerb due to accident

Toll Plaza Buildings All buildings shall be checked as per requirement of its different components as decided by the CME

Kilo Stones



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5.7 Relevant Surveys 5.7.1 Traffic Census Classified traffic volume count survey for 7 days at 3 locations on each road shall be conducted once in a year. This data shall be compared with the data as provided during detailed engineering design and shall be used for designing any functional/structural overlay of the pavement. The traffic surveys will be planned and programmed by the CME of the Zones/Departments. The responsibilities will be delegated to nominated engineers in turn to control the field operations and quality/extent of field data. A team of trained enumerators under the supervision of inspectors will collect the data. The inspectors will be responsible for the surveys, data collection and analysis. 5.7.2 Roughness Survey Surface unevenness/roughness of a pavement is essential to judge the functional performance of the pavement. This survey should be conducted every alternate year. The roughness surveys will be planned and programmed by the CME of the Zones/Departments. He will also be directly responsible to control the field operations and quality/extent of field data. An inspector who will be responsible for monitoring of the surveys, data collection and analysis will do data collection. This survey is conducted along wheel paths by using bump integrator or similar instrument of any standard make. The integrator instrument will be fixed and operated in accordance with the manufacturer’s instructions. The reading shown by the display unit, which gives the roughness in mm/km will be recorded for each kilometer. The data will be recorded along the wheel path while the vehicle moves at a constant speed of 32km/hr. Minimum two runs in each direction shall have to be conducted. The rating of the performance of a flexible pavement with bituminous concrete surfacing is made on the following basis:

Bump Integrator Value (mm/km)

Rating

<2000 Very Good 2000-2500 Good 2500-3500 Fair 3500-4500 Poor

>4500 Very Poor 5.7.3 Axle Load Survey Axle load surveys should be conducted at on random sample basis to cover commercial goods traffic in both directions. A few representative buses should also be weighed. The surveys should be conducted over a period of 48 hours (24 hours in each direction). The survey results are instrumental in the design of any functional or structural overlay.



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The axle load surveys will be planned and programmed by the CME of the Zones/Departments. He will also be directly responsible to control the field operations and quality/extent of field data. An inspector who will be responsible for monitoring of the surveys, data collection and analysis will do data collection. Help of the police will be required to stop and divert the vehicles on to the weigh pads. The equipment used is Portable Weigh Bridge System. Survey should be conducted as per the guidelines prescribed by the manufacturer. Data is recorded as per Annexure 6. 5.7.4 Benkelman Beam Deflection Test Benkelman Beam Deflection Test helps to judge the structural adequacy of the pavement and the need to overlay. The test should be carried out every year. The data is collected along the road at 25 meter staggered interval in both directions. The tests will be planned and programmed by the CME of the Zones/Departments. He will also be directly responsible to control the field operations and quality/extent of field data. Data collection will be done by a team of trained enumerators under the supervision of an inspector, who will be responsible for monitoring of the surveys, data collection and analysis. Help of the police will be required to stop and divert the vehicles during survey. To ensure that there is no major variation in the pavement temperature, it is recommended that the tests should be carried out between 6 AM and 11 AM before the pavement gets heated up. The equipment used is:

Standard Benkelman Beam with dial gauge 6-tonne truck with dual rear wheels Banners and red cones for traffic safety Glycerol and thermometer (0 – 100 degrees C) A portable tire pressure gauge Hand tools for making holes in the bituminous pavement for temperature

measurement. At the start of work on each day, the deflection beam will be checked for calibration using filler gauges of known thickness.

Benkelman Beam



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6. Maintenance Methods 6.1 Routine Maintenance in General Importance of routine maintenance cannot be over-emphasized. It is a question of “stitch in time” and is most appropriate to the present state of roads in Afghanistan. While there has been damage to the roads due to military actions over the period but the major reason for the present state is neglect in routine and periodic maintenance. Out of the total paved road network of 3000km, about 600km paved surface can even now be saved by resorting to routine and periodic maintenance and subsequent strengthening after 2-3 years. The maintenance activities for road works should be carried out twice in a year at appropriate times of the year depending on the terrain. A nominated engineer by the CME of the Zones/Departments will be responsible for co-ordination, execution and quality of maintenance activities. He will also decide on the required workforce and equipment for the activities. Various maintenance activities are discussed in detail in the following paragraphs. 6.1.1 Clearing Vegetation, Rubbish and Debris The activity shall be carried out either by hand or mechanical means. This involves control of grass, weeds, bushes and trees. Unwanted weeds and other vegetation shall be removed and the height of grass beyond a reasonable limit should be cut with a long blade to ensure proper sight clearances for the vehicles traveling on the road. Similarly bushes, hedges and tree branches shall be trimmed and cut to ensure proper visibility and road safety. This activity includes removal of all kinds of loose material lying on the road land arising out of different operational and maintenance processes by various agencies such as electricity, water, telephones etc. The spoils out of the cleaning operation will be stacked at short intervals along the road side and disposed off at places away from the road side so that the drainage ditches are not blocked. 6.1.2 Restoration of Rain-cuts and Eroded Embankment Slopes Rain-cuts often affect embankment slopes. These should be made good by replenishing with suitable earth and compacting. Rain-cut affected area should be cleared of all loose soil and benched. The width of the benches be at least 300 mm and extend continuously for a sufficient length. Height of the benches should be 150-300 mm. Fresh approved material Replenishing of soil before compaction



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should be deposited in layers not exceeding 250 mm loose thickness and compacted with optimum moisture content. The compaction should be carried out with plate compactors or rammers. 6.1.3 Landslide/Sand Dune Clearance: While landslides will occur during rainy season (e.g. Kabul-Jalalabad road) and snow melting (e.g. Kabul-Salang Tunnel road) in hilly areas, the sand dune shifting (e.g. Naibabad-Haritan road) will be frequent in some of the desert areas. Large landslides shall be cleared with bulldozers or other mechanical equipment. The same machines will be required for sand accumulated on the roads in desert areas. 6.1.4 Snow Clearance: Use of snow ploughs and special snow clearance equipment besides bulldozers will be required for clearance of snow. Special teams should be placed for these operations suitably in camps well before the winter sets in with adequate diesel, petrol, oils and lubricants besides spare parts for the specialized machines with well trained and experienced operators. Some of the roads such as Kabul - Salang Pass - Mazar-e-Sharif being the lifeline for traders and people, shall have to be kept open throughout the winters.

Flooded road; Bamyan, July 2005, Master Plan



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6.2 Routine Maintenance of Gravel Roads 6.2.1 General Good gravel road maintenance or rehabilitation depends on two basic principles: proper use of a motor grader (or other grading device) and use of good surface gravel. Everyone involved in gravel road maintenance must understand the correct shape of the entire area within the road’s right-of-way. The figure below shows a typical cross section of a gravel road. In order to maintain a gravel road properly, operators must clearly understand the need for three basic items: a crowned driving surface, a shoulder area that slopes directly away from the edge of the driving surface, and a ditch. The shoulder area and the ditch of many gravel roads may be minimal. This is particularly true in regions with very narrow or confined right-of-ways. Regardless of the location, the basic shape of the cross section must be correct or a gravel road will not perform well, even under very low traffic. 6.2.2 Erosion Control An often-repeated adage in the road construction and maintenance business is that “The three most important things to understand in building and maintaining roads are drainage, drainage, and drainage!” This certainly does get an important message across. But, too often, this critical issue is ignored when building and maintaining local roads. When drainage is poor, the best efforts to rehabilitate or maintain roads

will bring disappointing results. When water

C L

Fore slope

Back slope

Gravel surface Subgrade

Shoulder

Ditch

The Components of the Roadway Cross Section

Drainage problems; Mazar-e-sharif, Feb. 2005

Well maintained gravel road; Kandahar, Mar. 2005



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can be drained off of road surfaces and out of roadbed soils, the road will invariably become easier to maintain. When major reshaping is done outside of the traveled way, vegetation and ground cover will obviously be disturbed. This can lead to erosion of soil. The problem will vary depending on the region. In arid and semi-arid areas, the problem is small or nonexistent. Areas which receive frequent rains, have rolling or rugged terrain, and have highly erodible soils, are particularly vulnerable. When vegetative cover is disturbed, there are problems that can arise. While trying to eliminate problems, new ones can be created such as clogged culverts and blocked ditches, pollution of streams and lakes, and eroded slopes which can shorten the life of improvements. 6.2.3 Dealing with Corrugation The technical term is corrugation, but virtually everyone in the field refers to the problem as washboarding. This problem can bring more complaints than any other. It is very annoying to the driver and, when it becomes severe, can lead to loss of vehicle control. It is impossible to deal effectively with this problem if you do not understand the causes. Motorgraders are often blamed, but in reality, they seldom cause the problem. There are three primary causes: the driving habits of people, lack of moisture, and poor quality of gravel. Driving habits are clearly evident when you observe washboarding at intersections, going up or down steep hills, leading into or out of sharp curves and sometimes even near driveways. These are all places where drivers tend to accelerate hard or brake aggressively. This is a major cause of washboarding. Lack of moisture will encourage wash - board formation and prolonged dry weather can really aggravate the problem. This is because the crust that 6.2.4 Soft and Weak Subgrade

Although it is extremely important to remove surface and subsurface water from the

Corrugation or washboading

Soft and weak subgrade Spreading geotextile



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roadways, there are situations where water simply cannot be kept away. A good example is a section of road that passes through swampland or wetlands which naturally occur and cannot be drained. These areas will very often have weak subgrades, which cannot support heavy loads. Sometimes it is even hard to maintain the road for light traffic. The road will rut and potholes will be formed very quickly due to very poor soil support. This requires more than routine maintenance and reshaping if the problem is to be fixed permanently. Generally, there are only two solutions. One is to excavate and remove the weak, wet soil. Occasionally, the existing roadway is wide enough that after adding select material and shaping, the top width of the finished surface is adequate. In this case, undercutting will not be necessary. This “select material” will vary depending on what is available in the region. One thing is critical: it must be clean and drainable. The second method is similar, except a product called a geotextile or geosynthetic is added. These products are often called “fabrics” and “grids” in the field. Here the procedure is virtually the same as described before, but a fabric and/or grid is placed over the subgrade soil before the select material is brought in woven or non-woven fabric (geotextile) placed on the subgrade becomes a separator between the weak soil and the new material placed above it. 6.2.5 Motorgrader Operation The angle of the moldboard is critical to good maintenance. This angle is fixed on some grading devices, but on motorgraders it can be easily adjusted. It is important to keep the angle somewhere between 30 and 45 degrees. It is a challenge to recover loose aggregate. Operating speed in blading operations must not be excessive. This has caused problems on many roads. It is virtually impossible to do good work above a top speed of 5 to 8 kph. When the machine begins to “lope” or bounce, it will cut depressions and leave ridges in the road surface.



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6.3 Routine Maintenance of Flexible Pavement Bituminous pavement surface repairs are the predominant part of routine repairs and comprises of following items. 6.3.1 Filling of Potholes Potholes are bowl-shaped holes of varying sizes in a surface layer or extending to the base course caused by localized disintegration of material. The repair procedure is as under: (1) Marking out the area with chalk, by drawing a rectangle around the pothole. The area must be of regular shape and size and be adequate for rolling operation by suitable equipment. (2) Excavating the area until firm dry material is found, and trimming the walls of the pothole so that they are vertical. (Excavation could be done by providing a vertical saw cut with mechanical saw and then removing the material from the pothole with pick-axe and shovel and finally carting the removed material away in wheel barrows). The base of the area is trimmed such that it is flat, horizontal and free from loose materials. The base is tamped and compacted. A tack coat is provided to the horizontal and exposed vertical faces after proper cleaning of the excavated portion.

(3)The excavation is filled with selected well-graded bituminous mix, generally of the same type as the layer to be repaired. The material can be a cold-mix or hot mix material. (4)Material is laid in layers of thickness not exceeding 40 mm, and compacted layer by layer with vibrating roller, plate compactors or rammers. The last layer must be 1/5th the thickness of final layer proud, to allow for

Potholes in flexible pavement

Cutting vertical edge with mechanical saw

Excavating the area & trimming of walls

Removed material being carted away in wheel-barrows



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settlement or compaction. (5)The surface is compacted until the final surface is level. The repair is sealed to prevent any ingress of water. Various types of patch material generally used are at Tables 1 and 2 below.

TABLE 1

Open Graded Premix Patching

The material consists of a mixture of stone aggregates and binder. Aggregate: The stone aggregates of the following sizes and quantities specified below are recommended to be used for premixing. .

Aggregate Quantity (cum)

Normal size 13.2 mm (passing 22.4 mm and retained on 11.2 mm sieve) 0.18 Normal size 11.2 mm (passing 13.2 mm and retained on 5.6 mm sieve) 0.09 Total 0.27 Binder: It is recommended to use penetration bitumen as binder of a suitable grade as given below :

Binder Quantity (Kg)

For 0.18 cum of 13.2 mm nominal size stone at 52 kg bitumen per cum 9.5 For 0.09 cum of 11.2 mm nominal size stone at 56 kg bitumen per cum 5.1 Total 14.6

Mixing of material should be done in hot mix plant. The pre mixed material shall be spread by suitable means to the desired thickness, grades and cross-fall (camber). The area to be patched is cleared of all dirt and tack coat applied. As soon as sufficient length is spread, it shall be rolled with 8-10 ton roller. Patch material must not be laid in thicknesses > 40 mm. Each layer is compacted by vibratory roller or plate compactors before the mix cools to below 100 degrees centigrade. Seal coat must be applied on the top immediately after laying

Pothole repair procedure



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TABLE 2

Dense Graded Premix Patching Dense graded material is applied on relatively superior surface type. These mixes are not mixed materials but they comprise of mixture of binder, aggregates and filler and the mix design is done in the laboratory. Aggregate: Course and fine aggregates and the filler should be mixed in suitable proportion to obtain a final composition satisfying any of the two grading set forth below.

Percent by weight passing the sieve Sieve Designation Grading 1 Grading 2

20mm 12.5mm 10mm

4.75mm 2.36mm

600micron 300micron 150micron 75micron

Nil 100

80-100 55-75 35-50 18-29 13-23 8-16 4-10

100 80-100 70-90 50-70 35-50 18-29 13-23 8-16 4-10

Binder: The binder is recommended to be a paving grade bitumen. The quality of binder by weight of total mix shall be in the range of4-6 percent so that the following design requirement could be achieved. Design Requirement of Dense Graded Patch Mix Marshal Stability with 50 blows on each end of specimen 750 lb Marshal Flow – 0.01 inch 8-16 Per cent voids in mix 3-5 Per cent voids in mineral aggregates filled with bitumen 75-85

Mixing of material should be done in hot mix plant. The pre mixed material shall be spread suitable means to the desired thickness, grades and cross-fall (camber). The area to be patched is cleaned of all dirt and tack coat applied. As soon as sufficient length is spread, it shall be rolled with 8-10 ton roller. Patch material must not be laid in thickness > 40mm. Each layer is compacted by vibratory roller or plate compactors before the mix cools to below 100 degree centigrade.



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6.3.2 Patching of Local Areas Local areas showing defects like slippage, rutting, shoving, shallow depressions and crocodile cracking should be patched with premix or site mixed materials. The procedure adopted shall be:

(1)The area to be patched is marked out with a white chalk in a rectangular shape.

(2)Excavating the area until a firm layer of material is found, and trimming the walls of the hole so that they are vertical. The bottom is trimmed such that it is flat, horizontal and free from loose material. The bottom is compacted and a tack coat provided to the horizontal and exposed vertical faces. (3)Patch material is laid in layers not exceeding 40 mm. Each layer is compacted thoroughly with a roller or a plate compactor. The last layer must be 1/5th the thickness of final layer proud, to allow for settlement or compaction. (4)The surface is compacted until the final surface is level. The repair is sealed to prevent any ingress of water. Various types of patch material generally used are at Tables 1 and 2 as in the case of pothole filling.

Tack coat applied on the bottom and the exposed vertical faces



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6.3.3 Crack Sealing

Crack sealing is done for preventing the ingress of water into the underlying pavement layers. The types of cracks generally encountered are alligator cracks, edge cracks, joint cracks, reflection cracks, shrinkage cracks and slippage cracks.

Fog seal is used for sealing cracks less than 3 mm width. These crack sealers maintain a tightly sealed joint usually only as long as the pavement remains quite stationary both vertically and longitudinally. Once expansion or contraction or excessive vertical movement occurs, the effectiveness of the crack seal can be lost and cracks must be sealed again. The recommended material specification for fog seal is given in Table 3.

A bituminous binder cannot effectively seal cracks wider than 3 mm width alone. A slurry seal is more effective in such cases. Slurry seal is a mixture of fine aggregate, mineral filler and bitumen emulsion diluted with water to achieve a slurry consistency. The ingredients are mixed and spread evenly on a bituminous surface to fill the cracks. Recommended specifications of slurry seal are given in Table 4.

Alligator cracks more than 3 mm wide - Slurry Seal Treatment

TABLE 3

Fog Seal

Fog seal is an application of emulsified bitumen, without any aggregate cover for sealing fine hair cracks, like shrinkage cracks, or for rejuvenating oxidized bituminous surfaces. Areas having cracks of < 3 mm width are suitable for this treatment.

Emulsion shall be of slow-setting type and preferably applied at a rate of

0.5-1.0 liters per sq m using equipment like a pressure tank, flexible hose, spraying lance or bar.

Area to be treated is thoroughly cleaned with compressed air, scrubbers etc. The cracks are cleaned with pressure Air jet to remove all dirt, dust etc before applying emulsion.

Traffic is allowed on the surface after the seal has set to a non-tacky and firm condition so that the binder is not picked up by the traffic.



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Aggregate Grading for Slurry Seal

Percent by weight passingSieve Size 5 mm seal 3 mm seal 1.5 mm seal

9.5 mm 1004.75 mm 90-100 1003.35 mm 80-100 1002.36 mm 65-90 75-100 95-1001.18 mm 45-70 55-90 70-95

600 micron 30-50 35-70 55-75300 micron 18-30 20-45 30-50150 micron 10--21 10--25 10--3075 micron 5--15 5--15 5--15

Quantity of residual binder, 7.5-13.5 10--16 12--20%age by mass of aggregates

Approx. coverage rate (kg/sqm) 8--15 4--6 2--4

TABLE 4

Slurry Seal

Slurry seal is a mixture of emulsified bitumen, well-graded fine aggregate, Portland cement filler, and water. The mix is placed onto the cracked surface to be treated, spread and rolled. This application is for filling cracks wider than 3 mm and is appropriate for:

Repairing seriously raveled pavements. Repairing smooth or hungry surfaces. Rejuvenating oxidized and open textured bituminous surfaces. Improving the skid resistance.

Slurry seals are applied in thickness of 5 mm, 3 mm and 1.5 mm. The recommended gradation of aggregates for these thicknesses is:

The quantity of emulsified bitumen should be 180-250 litres/ton of dry aggregate. Cement up to 2% by weight of dry aggregates will be a beneficial additive. The ingredients are proportioned by weight and mixed in a slurry seal machine or a mechanical mixer. The mixed product should be slurry in a semi-fluid but homogeneous mass with no emulsion run-off.

The surface to be treated is prepared by removing any loose material, dust and vegetation. Potholes and depressions are patched and a tack coat applied @ 0.15 to 0.30 litres/sq m.

Application of slurry could be done by slurry seal machine or manually. For manual application, material is spread to a thin layer over the marked area, at a rate such that the cover of aggregates (dry mass equivalent) is 8-15 kg/sqm, 4-6 kg/sqm and 2-4 kg/sqm for 5mm, 3mm, 1.5mm thick work respectively.

A pneumatic tire roller making at least 6 passes then rolls slurry Rolling should commence soon after the slurry has set sufficiently to ensure that rutting or excessive movement does not occur. Adequate steps are required to avoid damage by traffic till after mix has cured sufficiently so that the slurry does not get picked up the vehicle tires.



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6.3.4 Repairs to Other Kinds of Faults Raveling

Raveled surface will require correction by adding more quantity of binder. The rate of application will depend on the condition of the existing surface and degree of hardening of the binder. If the raveling has not developed too far, the condition may also be corrected by application of Liquid Seal Coat. The recommended material specification for Liquid Seal Coat is at Table 5.

Table 5

Liquid Seal Coat The treatment consists of applying a coat of liquid bitumen and covering the same with aggregate. As the bitumen is required to penetrate through the cracks, the recommended binders are:

Cold application cut-back such as RC-3 or MC-3 Rapid setting emulsion

Quantity of Binder for 10 sqm

Sealing area is marked with chalk to a rectangular shape, swept clean and dried if necessary. A spray lance or a pouring can then applies binder, at the specified rate and application temperature. Covering aggregate is then spread by manual means at the following rate:

The cover aggregate is then rolled into position by a 8-10 ton steel wheel roller or with a vibrating roller. If a cutback is used, the finished surface should be closed to traffic till the binder has cured adequately to hold the aggregate in position. If emulsion is used the repaired portion can be opened to traffic in 4-6 hours.

B in d e r Q u a n t ity(k g /s q m )

C o ld A p p lic a tio n c u t-b a c k 9 .8(R C -3 o r M C -3 )R a p id S e tt in g E m u ls io n 1 0 .5 -1 5

A g g r e g a te Q u a n t ity(c u m /s q m )

N o rm a l s iz e a g g re g a te 6 .3 m m 0 .0 0 9p a s s in g 1 0 m m s ie v e a n d re ta in e d o n 2 .3 6 m m s ie v e



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Sand Blanketing of Bitumen Bleeding Areas Upward travel of excessive bitumen to the surface of a flexible pavement is termed as bleeding and makes the surface slippery particularly in the wet weather.

The treatment consists of applying a thin film of cover aggregates or sand (sand blanketing) depending on the severity of bleeding. These should be of small size (up to 5mm) clean and angular. Aggregate, sand or grit is spread or scattered by shovel or other means over the affected area. It is then leveled uniformly with light wooden spatula or any other method without disturbing the surface. Light rolling would help in fixing aggregate or sand to the film. Hungry Areas

The reverse of bleeding phenomenon is hungry areas where the binder has moved downwards and the aggregate is starting to be picked up by tires of the vehicles due to lack of adhesion to the bitumen matrix. This requires spot treatment with Fog Seal (Table 3 above refers). Damaged Edge

Edges of a paved road sustain damage if the side supporting shoulders are not firm. Repair consists of restoring the broken bituminous layers by local patching and restoration of shoulders. The area to be restored is marked for potholes and material inside the marked area is excavated and removed. The sides are cut vertically and the cut is filled with premix in layers not exceeding 40 mm and compacted. Refer Tables 1 and 2 above for various types of patch material.

Damaged edge



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6.4 Routine Maintenance of Rigid Pavement 6.4.1 Repairs to Rigid Pavement Compared to the flexible pavement, the rigid (concrete) pavement has much more life (almost 5 to 8 times), but the longevity is entirely dependent on the regular and proper routine maintenance. Also the funds generally required for the rigid pavement are almost negligible compared to the requirement of maintenance funds for the flexible (asphalt) pavement. The types of damages which generally take place in concrete pavement are on the joints (longitudinal, transverse and construction joints), spalling, edge cracking, and scaling. For the joints, it is imperative that these are resealed whenever required to ensure no ingress of water through them, thereby causing damages to the complete concrete slab. This small but crucial maintenance activity is an example of “stitch in time”. The sealant should be cost effective and of good quality, failing which bitumen and sand mix could also be used as a substitute. The latter has been put to good use on the first 43km of Herat-Torghadi road recently as also some stretches of the Kandahar-Herat road. (Both these roads were constructed in the early 1960’s by the Russians as concrete pavement. These have lasted for more than 4 decades in spite of inadequate and

even complete lack of maintenance in most stretches.)

Longitudinal and transverse cracks needing repairs

Cracks repaired with bitumen-sand mix on Herat-Torghandi Road

Scaling, cracking and breaking of concrete slabs on Herat-Kandahar Road



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6.4.2 Shoulder Maintenance The types of maintenance for unpaved (earth or gravel) shoulders are: (1)Restoring to original level and cross-section profile by regarding This is best accomplished by a motor grader. However, it must be ensured that the level of earth/gravel deposited on the shoulders after compaction and regarding is neither higher than the pavement (as it will result in lack of drainage outlet) nor be too low as to allow breaking/damage to the road edges. Potholes and unevenness in shoulders can be addressed manually on day-to-day basis. (2)Replenishment of shoulder material The work consists of making up the irregularities/loss of material on the shoulder to the design level by adding fresh approved soil/gravel and compacting it with appropriate equipment in layers not exceeding 250mm loose thickness. The finished surface should have a slope in conformity with the cross-sectional drawings.

Making good the shoulder material



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6.5 Routine Maintenance of Bridges and Culverts 6.5.1 Bridges and Culverts The maintenance activities for bridges and culverts like the road works should also be carried out twice in a year at appropriate times of the year depending on the terrain. A nominated engineer by the CME of the Zones/Departments will be responsible for co-ordination, execution and quality of maintenance activities. He will also decide on the required workforce and equipment for the activities. Various maintenance activities are discussed in detail in the following paragraphs. 6.5.2 Concrete Works: For concrete works in superstructures, substructures, foundations, retaining walls, abutments, wing walls, head walls etc. for both bridges and culverts, the following general maintenance procedures should be followed:

Cracks in cement concrete works should be maintained by injection of cement grout or epoxy resin into the cracks. Brief specification is at Table 6,

Replacement of spalled concrete be done as per Table 7,

Guniting or shotcreting in concrete works be carried out as per Table 8, and,

Corroded steel members should be painted or replaced based on the severity of the effect as per the directions of the Chief Maintenance Engineer.

Khulm-Kundos road; March 2005, Master Plan

Ahsan Gusala Bridge, Kabul, 2004



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TABLE 6

Sealing of Cracks by Injection of Epoxy Resin

The material for injection should be low viscosity epoxy resin, having the required characteristics of bonding with concrete and resistance to moisture penetration. Epoxy mortar or polysulphide resin may be used for sealing the surface. Recommended specifications of material for epoxy injection are:

(i) Mixing ratio of resin and hardener should generally be between 1:1 and 2:1 by volume subject to the manufacturer’s recommendation.

(ii) Solvents and thinners should not be the ingredients of mixed epoxy adhesives or their individual components.

(iii) Components be free of lumps or foreign material. (iv) Viscosity of individual components does not vary + 5% when kept in a closed

container at 25 degrees Celsius after 2 weeks. (v) Consistency requirement.

Material Standard Version cps Low viscosity Version cpsViscosity of mixed adhesive at (200-300) (100-190)25 degree CelsiusPot life of mixed adhesive at 1 hour + 15 minutes*25 degree CelsiusSet time of mixed adhesive at 3 - 6 hours25 degree Celsius* In the case of two components injection system, where resin and hardener get mixed atpoint of injection, pot life at 25 degrees Celsius shall not be greater than 15 min+10 min

Equipment for injection should be portable, positive displacement type pumps with interlock to provide positive ratio control of exact proportions of the two components at nozzle. The injection equipment should have automatic control capable of discharging mixed adhesive at any pore-set pressure within the prescribed limit and should be additionally equipped with a manual pressure control. Surfaces adjacent to cracks or other areas of application should be cleared of dirt, dust, grease oil efflorescence or other foreign matter by brushing/water jetting/sand blasting. Acids and corrosives should never be used for cleaning. Injection of epoxy adhesive should begin at lowest entry port and continue until there is an appearance of epoxy adhesive at the next entry port adjacent to the entry port being pumped. When epoxy adhesive travel is indicated by appearance at next adjacent port, injection should be discontinued on the entry port being pumped and entry port be sealed. Thereafter epoxy injection is transferred to next adjacent port where epoxy adhesive has appeared. Epoxy injection is continuously performed until cracks are completely filled. If port to port travel of epoxy adhesive is not indicated, the work is immediately stopped. Also in case the volume of the injected material is more than 2 liters for particular entry port, the work is stopped and specifications reviewed.



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TABLE 7

Epoxy Mortar for Replacement of Spalled Concrete

General Specifications: Pot Life : 90 minutes at 25 degree Celsius : 60 minutes at 30 degree Celsius : 45 minutes at 35 degree Celsius Bond Strength : 12 Mpa Tensile Strength 16 Mpa Sand content in mortar : In accordance with desired consistency Resins and hardener should be mixed prior to adding of dry filler. Ready to use mixed mortar be devoid of lumps of dry filler and have uniform color. Hand mixing could be done for total weight of 1 Kg or less. For quantities in excess – 400 to 600 rpm electric drill with jiffy mixer is required. Surface on which epoxy is to be placed should be free from rust, grease, oil, paint, asphalt, loose material, unsound concrete, dust or any other deleterious material. Since cured epoxy does not provide adequate bonding with any material, all overlay, whether epoxy or cement based, should be done within the pot life of the epoxy layer. Epoxy bonding agents should not be applied during rains or in the standing water. The surface must be dry. Epoxy primer coat be applied with the help of stiff nylon bristle brushes or hard rubber rollers or spray gun depending on the nature of surface and the extent of work area. Preferably the coating should be uniformly thick. Before the primer coat is fully cured, epoxy mortar is applied with trowels and floats. Interval between the application of primer coat and epoxy mortar is between 15/30 minutes depending on the ambient temperature. Seal coat is applied after 24 hours curing, after mild roughening of the surface mortar. The coverage of resin mix will depend on the system of resin used. However, as a guideline the coverage area should be as under:

(i) Primer Coat: 1 kg of resin-hardener mix covers an area of 3-6 sqm per coat depending on the concrete finish.

(ii) Epoxy Mortar: 1 sqm of surface requires 20-24 kg of epoxy mortar when laid to a thickness of 10mm.

(iii) Seal Coat: 4-6 sqm per kg of mix depending on the temperature of application.



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6.5.3 Masonry Works For both bridges and culverts, the following general maintenance procedures are followed for masonry works in foundation, retaining walls, wing walls and head walls etc.:

Re-pointing of masonry is done as a part of routine maintenance. Bulging masonry is mapped and measured with a plumb line and weep holes

provided for fill. Large cracks are mapped and treated with cement mortar. Any deterioration is protected by applying hard mortar, gunite or shotcrete on

the surface. All paints and galvanization is renewed as required after thorough cleaning of

the surface.

TABLE 8

Guniting/Shotcreting

Gunite is a mixture of cement, sand and water. It comprises of 100 parts of cement (ordinary portland cement), 300 parts of quartz sand, 35-50 parts of water and 2 parts of approved quick setting compound (all by weight).

Sand for guniting should comply with following gradation:

IS Sieve Percent Passing the SieveDesignation

4.75mm 95-1002.36mm 65-901.18mm 45-75

600 micros 30-50300 micros 10.-22150 micros 2.-8

For thick sections it may be advantageous to incorporate course aggregate in the mix provided adequate guniting equipment is available. Percentage of coarse aggregate may normally be kept as 20 to 40% of the total aggregate and the mix is then suitably designed. Water/cement ratio for guniting should be within 0.35 to 0.50 range by mass, wet enough to reduce the rebound. Drying shrinkage may be between 0.06 to 0.10%. The quick setting compound should be added at the nozzle with water just before guniting. Cement and sand should be batched and mixed, then conveyed through hose pipe with the help of compressed air. Density of gunite should not be less than 2000kg/cum, and strength not less than 25 Mpa. For effective guniting, nozzle be kept 60-150 cm away from the surface. It is desirable to moisten the green gunite for at least 7 days. Guniting works should not be carried out during windy or rainy conditions.



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6.5.4 Other bridge components Debris, Dirt and Vegetation Waterway should be cleared of obstructions, island formation and vegetation to prevent damage to the bridge. Deck drainage system Simple cleaning of carriageway, footpath, verges, joints, drain, gullies, gutter, etc. of trash and parasitic vegetation, manually or mechanically or by any other means Railing/Parapet/Crash Barriers Missing or distressed railing/parapets/crash barriers are replaced in time to maintain safe passage to vehicles and pedestrians. Painting of these is carried out as a part of routine maintenance. Footpath Slabs and Kerbs Missing and damaged footpath slabs and kerbs are replaced by new ones. Repainting of kerbs is carried out with approved paint. Bearings Removal of dirt between rocker surfaces and base plates is carried out. General maintenance of Elastomeric bearing or replacement of bearings if excessively damaged is also resorted to. Expansion Joints Cleaning of transverse grooves of expansion joints especially near the kerbs is carried out. All missing fixtures and fastening (bolts and steel parts) are replaced with approved ones. Wearing Course The riding surface should be free of potholes, cracks, depressions and disintegration by providing proper and timely maintenance. Road Surface at Approach Slab and Flexible Pavement Interface This interface on account of being a joint between the concrete approach slab and the flexible pavement is prone to breaking up or resulting in a depression due to impact of vehicles from one type of surface to another. In order to ensure a smooth riding surface it is necessary to maintain this interface by filling up the depressions as soon as they occur as a part of routine maintenance.

Waterway of bridge completely choked with debris & vegetation

A bridge without any railing parapets – unsafe for vehicles and pedestrians



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Slope and Bed Protection Stones which get disturbed or washed out should be timely replaced to prevent further deterioration. River Training The water course has a tendency to change due to various factors, thereby endangering the bridge structure. There is thus a necessity of carrying out river training works as and when required. This can be done by:

Providing walls made of steel or timber, sheet piles or stone filled crates. Protection of embankment by boulder pitching.

Substructure and Retaining Walls It is important to provide an adequate drainage method to drain the accumulated water immediately. Superstructure Clear off accumulated debris, dirt and vegetation on the superstructure. Foundation and Abutments Scouring around the bridge or the culvert foundation or abutment should be filled with mass concrete or any other material. Culverts Accumulated debris, silt and vegetation in the pipes of hume culverts should be cleared off as also in the proximity of the culverts.

Rehabilitated bridge on Kabul-Kandahar Road, 50km from Kandahar, Mar 2005



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6.6 Routine Maintenance of Drainage and Protective Works 6.6.1 Maintenance of Drainage and Protective Works The under-mentioned activities should be carried out twice in a year. The CME should be responsible for co-ordination, execution and quality of these activities. He should accordingly allocate workforce and equipment for the activities. 6.6.1.1 Lined and Unlined Drains: Cleaning The activity covers the manual removal of all loose soil, silt, high vegetation, materials and objects from the drain that could possibly interfere with water flow or cause an eventual blockage of drain. Disposal of the removed material should be away from the drain so that it does not fall back or wash back into the drain. Under no circumstances the removed material is to be spread on the road. For unlined drains, the drains should be cleaned to its established correct depth and profile with grass cover and no erosion. The grass should be cut short wherever it has grown long. Reshape/Re-grade/Deepen Drains The routine maintenance of unlined drains should be carried out manually or mechanically depending on the extent of work involved and resources available. Excavation should be done wherever required and the drain template be used for correct

Unlined drain being brought to shape by manual means

Unlined drain rehabilitation with excavator



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drain shape. Proper gradient should be achieved by excavation by suitable methods and simultaneous checks. The excavated material should be removed from the site and under no circumstances, spread on the road. Erosion Control A number of activities are required to prevent and repair erosion damage to drains. The following options should be considered:

Regrade/Realign Drain The drain may be extended to reduce the speed of water at the time of leaving the drain. The gradient should be as per the design or as per the site conditions, which may change. The drain may be realigned to follow the contour lines more closely until a location is reached where it may be safely discharged. Repair Lining The repair work should be carried out as soon as possible by removing the damaged portion and any debris from the drain. Backfilling with suitable material and compaction should be undertaken to correct levels after compacting the underlying soil. The drain section should then be laid as per the as-built drawings. Any open joint should be grouted with 1:4 cement mortar. Provide/Repair Scour Protection Unlined drains should be repaired by filling the effected areas with soil and turfing.

6.6.1.2 Catch Pit Routine maintenance should include the following activities:

Clearing and cleaning the catch pit sump. Replacement of missing covers and repairs of damaged ones. Minor repairs of catch pits with cement concrete. Cleaning of inlet and outlet pipes.

The disposal of the removed material should be done away from the catch pit so that they do not fall or wash back into it. The material should never be spread on the road. 6.6.1.3 Chute Drain Routine maintenance to include the following activities:

Clearing and cleaning of drain: Manual removal of all loose soil, silt, vegetation, materials and objects from the chute drain that could possibly interfere with water flow or cause an eventual blockage of drain.

Repair of chute drain, stone bedding or cut-off wall: For repairs or reconstruction of any chute drain component, as-built drawings should be followed for material specification and dimensions.

Replacement of eroded soil at outfall: This activity should be carried out manually.

The disposal of the removed material should be done away from the catch pit so that they do not fall or wash back into it. The material should never be spread on the road.



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6.6.1.4 Retaining Walls Weep holes should be cleaned and any damage of concrete works should be maintained. 6.6.1.5 Stone Pitching Routine maintenance should include the following activities: Replacement of missing stones To be carried out manually. Grouting loose stones Stones should be wetted thoroughly and 1:4 mortar should be placed between the stones of the pitching. Replacing eroded soil below the stones For soil erosion below the pitching, the stones should be first removed and then the soil below them should be compacted (add soil of approved quality if required). Then the stones be replaced in position.

Placement of longitudinal drainage pipe, Kandahar, Mar 2005



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6.7 Routine Maintenance of Miscellaneous Works The under-mentioned activities should be carried out twice in a year. The CME should be responsible for co-ordination, execution and quality of these activities. He should accordingly allocate workforce and equipment for the activities. 6.7.1 Traffic Signs Cleaning and repair activity of traffic signs should include:

Cleaning of information boards and posts. Repainting of posts and gantry. Replacing broken or bent support and signs. Replacing missing signs. Replacing missing nuts and bolts. Removal of signs no longer required (e.g. temporary signs after completion of a

maintenance activity to which they are related) Repair activities should be carried out in-situ or at a workshop depending on the severity of the damage. Traffic signs should conform to laid down specifications. 6.7.2 Road Markings and Road Studs Maintenance activity should be carried out manually or mechanically as suitable. The markings should conform to standard specifications or as per the as-built drawings. Replacement of reflective road studs should be done promptly if they are lost or damaged. These should then be protected by masking when surface dressing is being carried out. Suitable training in this regard is necessary to the allocated maintenance staff. 6.7.3 Distance Measure Stones and Culvert/Bridge Marker Posts Repair activities include:

Removal of vegetation grown around the stone. Repainting of stones as per specifications or given in the as-built drawings. Minor repairs of stones where required. Replacement of stone as a whole where required. Restoration of Culvert/Bridge Marker posts as per specifications or as per

as-built drawings.

Kabul-Charikar Road, Aug 2005



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6.7.4 Safety Barriers and Pedestrian Guard Rail Routine maintenance activity covers minor repairs like replacement of nuts and bolts, minor welding, painting and major repairs like replacement of safety barrier altogether. 6.7.5 Kerbs All missing and damaged kerbs should be replaced with new ones. Painting of kerbs should be done manually with approved paint conforming to specifications. 6.7.6 Toll Plaza Building Painting of the building should be carried out as a part of routine maintenance. All maintenance works should be done as per procedures of maintenance of concrete and masonry works as discussed in this chapter earlier.

Road Construction Material Testing Laboratory of MPW in Kabul, Feb 2005



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6.8 Periodic Maintenance Periodic maintenance is necessary as per laid down design parameters and when taken on in time, ensures longevity of the pavement and structures. Activities as given in following paragraphs are required to be undertaken. 6.8.1 Functional Overlay When the pavement distress parameters such as cracking, potholes, rutting, raveling cannot be handled through routine maintenance due to its severity and extent, it is tackled by functional overlay. On the other hand if roughness index exceeds 3500 mm/km or the surface becomes very smooth, functional overlay should be resorted to. The periodicity of application of this type of overlay should be judged by HDM model. Functional overlay should be done with 25 mm asphalt concrete as per specifications. 6.8.2 Strengthening Overlay Based on the designed life of the pavement as also close monitoring of the traffic loading and pavement strength, the need to strengthen the pavement would arise. The thickness and types of overlay are determined by carrying out (i) traffic census, (ii) axle load tests and (iii) pavement deflection tests such as Benkelman Beam test. Analysis through HDM model should also be done to calculate the periodicity of application of this type of renewal layer. 6.8.3 Repairs to Rigid Pavement Full depth repair would be required as part of Periodic Maintenance. The need for such repairs arises for (i) deteriorated joints, (ii) corner cracks, (iii) blow-ups, and (iv) large spalls etc. It is applicable for both plain and reinforced concrete pavement provided with dowel joints. The full depth repairs involve cast in-situ Portland cement concrete. The dimensions of repair can play a significant role in its performance. A minimum length of 2m and a full lane width repair is recommended incase of repairs with dowels and tie bars. If the repairs are longer than 4.5m, it would require an intermediate joint or be provided with reinforcement. If the repair area extends up to an existing joint or crack (within 2m), about 0.3m on either side of the joint should also be included as repair area. Cracks that are more than 3m from the joint can be individually repaired but when several cracks are closely spaced, the entire portion of the slab should be replaced. The performance of the full depth repairs is influenced by a proper jointing between new and old concrete. For this, smooth faced sawed transverse joint is recommended. Tie bars and dowel bars have to be used to achieve load transfer across transverse repair joints. 6.8.4 Drainage and Protection Works If routine activities are inadequate, then consideration should be given to the periodic maintenance, which will include collection of hydrological data wherever necessary and redesign. 6.8.5 Provision of New Drains



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Where side drains carry too much water or where erosion occurs frequently, the cross-section of the drain (for lined or unlined drains) should be redesigned based on new hydrological data collection and then implemented as a periodic maintenance activity. 6.8.6 Reline/Lining Drain When the unlined drain gets frequently damaged, it should be converted to lined drain. Also this activity should be carried out where previous lined drains are excessively damaged due to settlement or erosion.

Road maintenance machinery at MPW Kabul Construction Machinery Center, Feb 2005



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6.9 Safety /Traffic Management during Maintenance 6.9.1 Principle of Safety and Traffic Management During Maintenance The principle of safety and traffic management during the maintenance works is basically to ensure that, the road user as well as the personnel involved in maintenance works should not be exposed to any dangers or hazards while implementing maintenance operations. Also the delays and inconvenience to the traffic should be as minimal as possible. The above principle could be achieved by the following means: (1) For minimizing the traffic hazards and inconvenience, temporary road signs and traffic control should be well planned and put in place. (2) Standard road signs in good and clear condition should be displayed in a proper and standard layout, so as to give the drivers’ sufficient time to understand and react to the information displayed on the sign. (3) Confine the maintenance operations to small lengths of say 30m and in half pavement width, leaving the other half for the traffic to move freely. However, it may not be always possible to work in half width or 30m lengths. In such cases the maintenance works are generally divided into 4 categories from the point of view of safety and traffic control as follows:

Repairing of edges of the carriageway, shoulders, cleaning out drains, cutting grass etc. where carriageway is not affected.

Repairing carriageway restricting to one lane while traffic can be allowed on the other lane.

While working on the centre line such as centre line marking/painting, the traffic should be restricted on either side by posting adequate signage.

Total closure of road necessitating use of diversion due to widening/reconstruction of an existing cross drainage works for construction of a new structure or due to breach or damage to existing road or cross drainage works.

6.9.2 Workers Safety (1) Workmen must be adequately trained in the use of their tools and plant. (2) For workmen using bitumen, gum boots, spectacles etc. must be given. (3) Safety jackets should be provided to workers involved in maintenance activities. (4) The work site should have first aid kits and the first aid training be imparted to the workers.

6.9.3 Road Users Safety



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(1) As far as possible, the materials, plant, equipment and machinery should be collected / installed / parked in places sufficiently away from the berms in the available road-land. No material should be collected nor any equipment or machinery installed/parked on berms near the curves. (2) Caution sign boards, flags, adequately marked used drums etc. be placed at the work site and specific workers (women could be employed for such jobs to give gender parity in road construction activities) be nominated for traffic safety. (3) Machinery should be parked if not in use at appropriate places with red flags and red lights on. (4) Minimum quantity of material should be stocked at site to avoid its becoming a traffic hazard. (5) All signs, lights, barriers and other traffic control devices should be kept maintained till such time that the traffic is restored to normal. 6.9.4 Works on Edges and Shoulders Before the commencement of work, all warning signs should be installed such as (i) “Work in Progress”, (ii) Speed Limit signs placed 200m before approaching the work area and (iii) “Restriction Ends” sign displayed 200m beyond the work area on the hard shoulder. When the work is completed, these signs should be removed. 6.9.5 Traffic Restrictions At times the traffic is to be restricted to one lane only due to repairs being taken up on each lane such as major patch repairs or overlay etc. The cautionary and warning signs should be installed before the commencement of the works in the following sequence:

“Work in Progress” sign be put 200m before the work site. “Narrow Road Ahead” should be put at 100m ahead of the work site. “Keep Left/Right” sign should be placed at the commencement point and next to

the barriers on either end of the work area. Barriers should be placed on both sides of the work area. Painted drums should be placed at 10m intervals for guiding traffic. In the

approaches these may be kept in tapered manner. “Restriction Ends” sign should be installed 200m beyond the work area.

Use of painted drums, Road Markers and flags carried by woman for traffic safety



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In addition to the above. A watchperson should be present at the barrier to control the traffic at all times. Police assistance may be sought for in case of need.

Necessary lighting arrangements should be in place during night with flashing lights. In addition alternate black and white diagonal strips should be marked for effective advance warning, preferably with reflection type paint.

6.9.6 Traffic Arrangement for Repairs of Cross Drainage Structures Following instructions are recommended when undertaking these works: (1) Traffic should either go over part width of the structure or a temporary diversion, depending on the site conditions. The former method should be used as far as possible, especially when the work could be conveniently carried out in half width at a time and there are no undue problems in channeling the traffic through the available road width. In both cases, the work should be so planned that the repairs to the cross drainage facility is over in the shortest possible time, following properly conceived repairs and maintenance execution schedules. This will be facilitated if all materials and other equipment are collected at site in advance before the work actually commences. (2) Both-way traffic operation on a carriageway should be established whenever the traffic is to be passed over part width of the structure. This should be done with the help of a flag person and proper road sign, positioned on the opposite sides, who should be on duty during all hours. For the regulation of traffic the flag persons should be equipped with red/green flags and lanterns/lights. (3) At the points where traffic is to deviate from the normal path (whether on temporary diversion or part of the carriageway), the channel for traffic shall be clearly marked with the aid of pavement markings, and painted drums or a similar device. At night, the passage shall be delineated with lanterns or other suitable light source. To enhance night visibility, reflection-type paint may be used for the painting of markings and drums. (4) Strong barriers should be provided and maintained. (5) On both sides, suitable regulatory/warning signs shall be installed for the guidance of road users. On each approach at least 2 signs should be put up, one close to the point where transition of carriageway begins and the other about 120m away.

資料no.f-7 · road maintenance manual for afghan government engineers 23 november 2005 ministry...

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