b/c analysis of seismic resist building to non-engineering building techniques with retrofitting...

7/30/2019 B/C analysis of Seismic resist Building to Non-Engineering building techniques with Retrofitting Cost

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TRIBHUVAN UNIVERSITY

INSTITUTE OF ENGINEERING PULCHOWK CAMPUS

TITLE PAGE

B/C Analysis Of Retrofit And Earthquake Resistant Techniques

With Existing Conventional Techniques

by

Ram Mani Ghimire (068/MSD/363)

Ram Prasad Neupane (068/MSD/364)

Sweta Amatya (068/MSD/369)

A PROJECT REPORT

SUBMITTED TO THE DEPARTMENT OF CIVIL ENGINEERING

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE

DEGREE OF MASTER IN

DISASTER RISK MANAGEMENT

DEPARTMENT OF CIVIL ENGINEERING

LALITPUR, NEPAL



ACKNOWLEDGEMENTS

This research would never have carried out without the contribution of many individuals and

organizations, to which we have the pleasure of expressing appreciations and gratitude.

First of all, we would like to express our sincere gratitude to our supervisor Dr. J ishnu Subedi

for his valuable suggestions, indelible encouragement and guidance during the project work. I

extend my gratitude to all faculty members and colleague of Disaster Risk Management

Program, Pulchwok Campus, for their comments, suggestions for the study. We are also very

grateful to Asso. Prof. Hari Darshan Shrestha and Mr. Nagendra Raj Sitoula, Program Co

ordinator, Disaster Risk Management, IOE, Pulchowk Campus for providing us the valuable

suggestions during our study period. We would like to thank all our friends and colleagues for

their productive discussion and constructive suggestions, which helped in creative and

conclusive thinking during our study period.

Finally, we would like to thank all family members for their continuous inspiration, support and

affection throughout the study period and thanks to all those unmentioned who helped us

directly and/or indirectly in completion of this thesis work.



ABSTRACT

In the context of Nepal also, disasters is one of the major concerns for development effort. Cities

like Kathmandu have been urbanized but not in a way to enhance development, but rather to

invite disasters. On the other hand, these built up structures has created concrete jungle in urbanset up which are not even properly built in terms of engineering perspective. On top of that most

of the buildings residing on it are not well structured due to weak implication of building code.

This has led to the threatening fact of being trapped during disaster such as earthquake.

This study could assist in clear visualization of importance of building code in terms of

economic as well as safety perspective which can ultimately help to regulate building code in

practicality.

Main objective of our project is to evaluate the different technologies of construction i.e.

Conventional techniques, Earthquake resistant techniques(MRT followed) and retrofit

techniques in terms of monetary value. And main aim of making the urban dwellers convinced to

use more safer techniques(MRT and Retrofit) is based on benefit and cost analysis. On the basis

of European Damage Grade Scale the loss and damage due to different level of earthquake is

considered and this loss amount in different construction techniques analyzed and compared

with the extra investment for changing Non MRT building to MRT or Retrofitted. The total cost

was composed up of the major components like Structural, Non Structural, Service andFunctional. Different components like Structural, Non Structural, Service and Functional are

considered and comparatively analyzed in terms of money. Comparative analysis finally provide

us with the distinct figure of per unit cost of each techniques and benefit cost ratio of two

techniques with the conventional one providing us the strong base to inspire people for Building

Code implementation.



By:RamMani Ghimire, RamPrasad Neupane, Sweta Amatya

i

TABLE OF CONTENTS

TABLE OF CONTENTS ................................................................................................................. i

CHAPTER 1 ................................................................................................................................... 1

1.1 INTRODUCTION ................................................................................................................ 1

1.2 RATIONALE ........................................................................................................................ 2

1.3 MAIN OBJECTIVES ........................................................................................................... 2

1.4 SCOPE OF THE STUDY ..................................................................................................... 3

1.5 LIMITATION ....................................................................................................................... 3

1.6 METHODOLOGY ............................................................................................................... 4

CHAPTER 2 ................................................................................................................................... 5

2.1 CURRENT CONSTRUCTION TREND AND CONVENTIONAL BUILDINGS ............. 5

2.2 MRT AND MRT FOLLOWED BUILDINGS ..................................................................... 5

2.3 RETROFITTING AND RETROFIT BUILDING ................................................................ 6

2.4 DAMAGE GRADE .............................................................................................................. 9

2.5. BENEFIT-COST ANALYSIS ........................................................................................... 11

CHAPTER 3 ................................................................................................................................. 12

3.1 COST ANALYSIS OF MRT FOLLOWED BUILDINGS ................................................ 12

3.2 COST ANALYSIS OF NON-MRT BUILDINGS ............................................................. 17

3.3 COST ESTIMATION OF RETROFIT BUILDINGS ........................................................ 21

3.4 FUNCTIONAL COST ANALYSIS ................................................................................... 24

3.5 DAMAGE GRADE ANALYSIS ....................................................................................... 25

CHAPTER 4 ................................................................................................................................. 32

4.1 COMPARATIVE ANALYSIS ........................................................................................... 32

4.2 CONCLUSION ................................................................................................................... 35




ii

REFERENCES ............................................................................................................................. 37

ANNEXES ....................................................................................................................................... i




1

CHAPTER 1

1.1 INTRODUCTION

Disasters are situations or events which overwhelm local capacity, necessitating a request tonational or international level for assistance. Disasters and the way their risk is managed have

become the subject of increasing research and debate in recent years. This heightened interest is

because of the fact that the world has witnessed more disasters in the recent years and the people

have become more vulnerable to them.

In the context of Nepal also, disasters is one of the major concerns for development effort.

Urbanization, which is understood as a milestone towards development, is also increasing

disaster risk in Nepal.. Cities have been urbanized but not in a way to enhance development, butrather to invite disasters.Those open spaces and circulation routes have been engulfed by built-

structures. On the other hand, these built up structures has created concrete jungle in urban set up

which are not even properly built in terms of engineering perspective. This has lead to the

threatening fact of being trapped during disaster such as earthquake.

On the other hand, it is the known fact that Nepal lies in 11th position in earthquake prone

country. On top of that, those un-engineered built-up structures have enhanced threat to life of

people during disaster. People tend to build such structures due to lack of awareness regarding itsconsequences. There are many such buildings which lack proper structure that can withstand

earthquake shocks in urban set up. This depicts on the fact that“Earthquake does not kill people,

building does”.

Houses are one of the basic needs of people all over the world and humankind is constructing it

from the start of civilization. Although the technology has been evolved from long time, the

buildings are often exposed to different kinds of hazards. In Nepal, people intend to make their

houses aesthetically beautiful and functionally useful, but the houses often lack necessary

provision for safety to disasters like earthquake. People prefer to construct reinforced concrete

structures with their traditional knowledge which, although suitable for traditional materials,

makes the structure vulnerable to earthquake. The main rational behind such construction is that

earthquake safer buildings are not economical.




2

There are many existing buildings which are not safe during earthquake and require

strengthening and retrofitting. The purpose of this project is to carry out the cost benefit analysis

of different reinforced concrete (RCC) structures constructed using conventional and earthquakeresistant technology and also to obtain cost required for retrofitting of the buildings.

The project area under our study is Kathmandu valley. There are different typologies of

buildings in Kathmandu from historical time to present. We have considered the only the

residential RCC structures less than three storey. The buildings were sampled as per building

typology but not as per location basis.

1.2 RATIONALE

In terms of disaster perspective, urban areas are in vulnerable condition. On top of that most of

the buildings residing on it are not well structured due to weak implication of building code. This

study could assist in clear visualization of importance of building code in terms of economic as

well as safety purpose which can ultimately help to regulate building code in practicality.

1.2 MAIN OBJ ECTIVES

The main objective of the project work is compare cost of construction of RCC structure with

conventional technology and with technology and specifications defined in Nepal Building Code

with Mandatory Rule of Thumb (MRT). The project work also analyzes the cost requirement for

retrofitting of the structures which are not safe during earthquakes.

The specific objectives are as follows:

• To assess the structural, non-structural and functional cost for different buildings in

Kathmandu

• To assess the cost required for construction of following types of buildings:

Conventional Building (Non-MRT Building)

MRT Building

Retrofit Building




3

• To conduct comparative cost analysis of above mentioned buildings in terms of their

structural, non-structural and functional

1.4 SCOPE OF THE STUDY

It has been felt that buildings on urbanscape have not only taken away the essence of real

urban beauty rather unengineered buildings are intending to invite risk at the time of disaster.

On the other hand people are much more intended towards conventional building in terms of

initial cost. So, the project will focus on assessing the benefit cost analysis which can help to

figure out actual benefit incurred by different construction techniques.

1.5 LIMITATION

• Analysis has been carried out for damage grade analysis which is majorly based on

European Macroseismic Scale (EMS-98)

• Damage percentage of structural, non-structural and functional entity concerning

damage grade are based upon literature

• Study focuses on residential buildings only

• Minimum sample size has been considered since detail rate analysis of samples has to

be carried out in a short period of time.

• Retrofitting estimates are only based on ‘Draft report of Retrofitting Guidelines’ by

CoRD, MRB and UNDP




4

1.6 METHODOLOGY

Study has been carried out within research criteria which are better explained through

following flowchart:

B/C Analysis of Retrofit and Earthquake Resistant Techniques withExisting Conventional Techniques

Literature Review

Data Collection

Primary Data• Non- MRT Building• MRT Building

Secondary Data• Retrofit Building Guidelines• Damage Grade• NBC-201(MRT)

Data Processing• Cost Estimation

Data Analysis• Cost Comparison • B/C analysis

Final Report




5

CHAPTER 2

2.1 CURRENT CONSTRUCTION TREND AND CONVENTIONAL

BUILDINGS

Peeping into the history of architecture of Nepal, building got its shape with load bearing

structure with brick and mud mortar in it. With the pace towards modernity such trend

has been changed into reinforced concrete framed structure in urban and semi-urban areas

of Nepal. For the last 15 to 20 years there has been rise in reinforced concrete (RC)

framed structure. Most of these buildings have been built on the advice of mid-level

technicians and masons without any professional design input. On the other hand, if it is

designed with engineering perspective also it is limited till municipality procedure only to

get building permit. But on ground building is strengthened with the advice of mid-level

technicians.

Due to such reason, these building have been found to be most significantly vulnerable to

a level of earthquake shaking which may result into loss of life and property at the time

of earthquake.

2.2 MRT AND MRT FOLLOWED BUILDINGS

Construction trend in present context reflects on the fact that buildings are of

unengineered construction and it has not been built as per structural consent, inviting

vulnerability and loss of life and property. In order to address these consequences

Mandatory Rules of Thumb (MRT) has been developed by Department of Urban

Development and Building Construction.

MRT building is one which uses the sizes and detailing of structural and non-structural

elements, including the amount of reinforcement, which has been pre-established using

standard design procedures for the given condition. All the buildings constructed by

following requirements of MRT can be called as Pre-Engineered Building.

Main objective of MRT is to provide ready to use dimensions and details for various

structural and non-structural elements for upto three storied reinforced concrete framed,




6

ordinary residential buildings commonly being built by owner-builders in Nepal using

brick infill wall.

Standard design Criteria followed by MRT are as follows:

• Building should have regular column- beam with reinforced concrete slabs for

roof and floors

• Area of slab panel shall not be more than 13.5 sq.m.

• Maximum height of the structure should be 11m or 3 storeys whichever is less.

Within 11m height there may be an additional storey of smaller plan area whose

area should not exceed 25% of the typical floor area

• Foundation shall be at uniform level

• Sill and lintel band must be provided

• Strap beam must be provided at foundation

• Plinth area should not be more than 1000 sq.ft.

• Column to column span should not be greater than 4.5m X 3m

2.3 RETROFITTING AND RETROFIT BUILDING

Buildings are of varied category and their coping capacity differs with its structural

stiffness. Considering the seismic capacity of the buildings, response of old as well as

unengineered buildings are considered to be vulnerable. Therefore, to re-strengthen such

buildings additional structural strength is added with added reinforcement and concrete

where needed. This procedure is called Retrofitting.

Retrofit can be carried out in both reinforced as well as load bearing structures. Retrofit

option for RC structures is costlier than in load bearing structure. Different techniquesused for seismically deficit RC structures are as follows:

a. Jacketing of structural members

b. Addition of extra structural members

c. Addition of energy dissipation device




7

a. Jacketing of structural members

Various methods of jacketing of structural members are as follows:

i. Concrete Jacketing:

Enlargement of structural members such as columns / beams section by placing

reinforcement around its periphery and then concreting it is called Concrete Jacketing. It

increases structure size and stiffness.

ii. Steel Jacketing:

Jacketing of columns / beams with steel angles, band and channels are called Steel

Jacketing. It does not increase the size of the structural members whereas it increases its

stiffness.




8

Fig.Steel J acketing

iii. Fiber reinforced polymer Jacketing:FRP jacketing is the modern technology of Jacketing reinforced concrete.

Retrofit with FRP panel can be done with much ease. These are excellent

option because of their high tensile strength, light weight, resistance to

corrosion, high durability and ease to install.

b. Addition of extra structural members:

In this technology, shear wall is added in between column. Shear wall is

constructed from the foundation level. Instead of this, column bracing could also




9

be used.

c. Addition of energy dissipation device:

Energy Dissipation Device is Passive Seismic Control System. Viscous fluid

damper and tuned mass dampers are passive seismic control system.

PhotoReferences: Seismic Retrofitting Guidelines of Building in Nepal (UNDP, CoRD and MRB &

Associates “Proposed Draft report”)

2.4 DAMAGE GRADE

Post earthquake has numerous effects ranging from social to physical effect. Among

physical effect damage on building is the one. There is various kind of damage that is

found on structure and damage grade helps in describing the building damage patterns by

seismic vulnerability. This helps investigators to classify building damaged without a

gross error.

The Earthquake Engineering Research Institute (EERI) proposed the guidelines for post-

earthquake investigations for the purpose of improving the science and practice of

earthquake engineering and earthquake hazard reduction. According to EERI damage

grade has been classified on six different categories for different types of buildings

ranging from masonry, wood frame, and reinforced concrete with moment-resisting

concrete frame. Among these RCC framed structure has been categorized as enlisted in

table below:




10

Damage rank Architectural Institute of J apan RC buildings

Rank 0:No damageRank 1:Negligible damage (Hair line cracks in columns and beams of frame)Rank 2:Slight damage (Shear cracks in non-structural walls)

Rank 3:Moderate damage (Shear cracks in columns and beams and instructural walls)Rank 4:Major damage (Spalling of concrete cover, Buckling of reinforced rods)Rank 5:Collapse (Collapse of total or parts of building)

1. Fall of pieces, 2.GF failure, 3.Mid-floor failure, 4. Upper floor failure, 5. Pancake

collapse 6. Multiple factures

Fig.: Typical damage pattern of reinforced concrete with moment-resting concreteframe buildings

In the study carried out damage grade has been categorized into three classes as given in

table below:

Damage Grade Based on European Macroseismic Scale:

Percentage of Damage in differentcomponents

S.N.Category of

Damage Range of AverageDamgae

Structural

NonStructural

Services

Functional

damageindex Index

1

Minor to

ModerateDamage 0-0.2 0.1 0% 20% 0% 0%

2Moderate toheavy Damage 0.2-0.6 0.4 20% 60% 40% 40%

3 Major Damage 0.6-1 0.8 60% 100% 100% 100%




11

2.5. BENEFIT-COST ANAL YSIS (B/C Analysis):

Cost benefit analysis (CBA), sometimes calledbenefit–cost analysis(BCA), is a

systematic process for calculating and comparing benefits and costs of a project, decision

or government policy. CBA has two purposes:

1. To determine if it is a sound investment/decision (justification/feasibility),

2. To provide a basis for comparing projects. It involves comparing the total

expected cost of each option against the total expected benefits, to see whether the

benefits outweigh the costs, and by how much.

The benefit cost ratio for our case is calculated as follows:

(Loss in Non MRT - Loss in MRT Buildings)

B/C Ratio= (Difference between MRT and Non MRT Cost )

http://en.wikipedia.org/wiki/Government_policy

http://en.wikipedia.org/wiki/Government_policy




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CHAPTER 3

3.1 COST ANALYSIS OF MRT FOLLOWED BUILDINGS

During the study, 6 MRT building has been considered. Among them 3 of them were

detail estimated and three of them were analyzed from questionnaire with owner,

contractor and engineer.

On the field following features has been found in MRT buildings:

• Column spanning : 10’-9” to 14’-9”

• Column size : 9” X 12”

• Footing size : 5’ X 5’ X 5.5’

• Beam size with slab: 9” X 1’-2” and 9” X 1’5”

• Slab thickness : 5”

• Reinforcement Detail :

Column : Main Bar : 4-12dia + 4-16dia, 8-16dia, 6-16dia

Beam : Main bar : 4-16dia +2-12dia

Stirrups : Column: 8dia-4L

: Beam: 8dia – 2L

Slab : Main bar: 10dia @6” c/c ; Distribution bar : 8dia @ 6”c/c

Top bar 10 dia, @ 12”c/c and binder 8 dia.@ 9”c/c




13

S.N. OWNER

LOCATION

BUILT-UP AREA

PLINTHAREA

NO.OF

STRUCTURAL

NON-STRUCTURAL

SERVICE COST

AVERAGE

NAME (S.FT.) (S.FT.)STOREY

COST(RS/SQ.F T.) COST (RS) (RS) (RS)

1BHUSANGAUTAM

BALUWATAR 2420.56 915 2.5 1119.92 1280.70 389.37

2789.99

2ABHAYA YADAV

GAURIGHAT 2370.56 915 2.5 1207.74 2425.27 439.56

4072.57

3BHABANA THAPA NAXAL 3203 1291 2.5 1239.24 1143.08 357.35

2739.67

4SHYAMPAUDEL

DHUMBARAHI 3639 1072 3.5 1236.60 1400.00 398.46

3035.06

5NARAYANSAPKOTA

BALUWATAR 2706 1111 2.5 1318.55 1390.00 406.50

3115.06

6 ENGINEER

DHUMB

ARAHI 3000 810 3.5 1163.33 1206.67 233.33

2603.

33

AVERAGECOST 1214.23 1474.29 370.76

3059.28

Fig. MRT followed buildings

Today generally new constructions are made following the codes and standards prepared.

During our field visit we collect information from three areas of concerns i.e. home

owners, contractors, consultant engineers. Some buildings were estimated in details as

shown below to find out what amount of cost is incurred in construction by following the

MRT guidelines. Generally we found that the view of people is changing from past to

present for making their structure safe and resilient and they are referring to engineer’s

suggestions and supervision during the construction period. We can take it as a

progressive step which would help all the urban residential to learn from them and




14

contribute to urban resilience of Kathmandu valley. Following the above chart we can

analyze that, the most important component on which people spend more is on Non

Structural items like floorings, finishing, paints, plasters, architectural items etc. More

than structural they spend more on non structural and functional items which would

create a great loss of their physical properties if the buildings are not constructed

following codes and standards i.e. MRT for our case. Hence it’s the time to convince

them to spend little more on structural components and follow the MRT standards so that

much of their properties are saved during the disasters. The main conclusions that can be

drawn from above table are;

• The nonstructural cost is the main component of total cost of the building

• Average total cost for MRT followed building is found to beRs 3059.28/sq.ft of built up area.

• In an average non structural cost is the main contributor for the total cost of

building.

• Buildings are taken or sampled not as per location but as per building typology

and requirements of the project objectives.

Fig. Cost components contribution to total cost in MRT buildings(per sq.ft.)




15




16

f ig. Typical Cross sections of existing structure

The detail of estimation and rate analysis is provided in the annex of the report.




17

3.2 COST ANALYSIS OF NON-MRT BUILDINGS

During the study, 5 NON-MRT building has been considered. Among them 3 of them

were detail estimated and two of them were analyzed from questionnaire with owner,

contractor.

During the field visit following features have been found in MRT buildings:

• Column spanning : 10’-0” to 14’-0”

• Column size : 9” X 9”

• Footing size : 4’ X 4’ X 4’

• Beam size with slab: 9” X 1’-1”

• Slab thickness : 4.5”

• Reinforcement Detail :

Column : Main Bar : 4-12dia, 6-12dia

Beam : Main bar : 4-12dia +2-12dia, 4-12dia

Stirrups : Column: 6dia, 7dia, 8dia-2L

: Beam: 6dia, 7dia, 8dia – 2L

Slab : Main bar: 10dia @6” c/c ; Distribution bar : 8dia @ 6”c/c

The information collected is summarized as below:

S.N. OWNER LOCATION

BUILT-UPAREA

PLINTHAREA NO. OF STRUCTURAL

NON-STRUCTURAL

SERVICECOST AVE

NAME (S.FT.) (S.FT.) STOREYCOST(RS/SQ.FT .) COST (RS) (RS)

1

RENUKA

DEVIPANDEY BALUWATAR 2638.00 858.00 3 791.51 1364.51 370.00 2526

2LAXMANSHRESTHA JORPATI 2800.00 1114.00 2.5 785.16 1364.51 370.00 2519

3

SHREEKANTAGHIMIRE KUPONDOLE 600.00 600.00 1 1146.28 1247.51 370.00 2763

4KESARISHRESTHA DHUMBARAI 2548.00 1019.00 2.5 765.13 1380.00 370.00 2515




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5RAMESHSAPKOTA DHUMBARAI 2100.00 840.00 2.5 1020.59 1280.99 370.00 2671

AVERAGECOST 901.73 1327.50 370.00 2599

We have visited different places of Kathmandu to see the residential buildings generally

less than three story. During our survey for already built buildings in different locations

we found different thoughts of people on the techniques of construction and their interest

for making structure safe enough to resist earthquake. Some people’s view about the

importance of MRT was found to be positive and convinced but some people do not think

it necessary to follow MRT because it increases the cost by more amount than the

prevailing rate they are constructing with. Following the above chart we can analyze that

the most important component on which people spend more is on Non Structural itemslike floorings, finishing, paints, plasters, architectural items etc. Although their building

is complying the codes and standards or not it is observed that costly nonstructural items

are used for fine and finished external looks and so on. The main conclusions that can be

drawn are;

• Non-MRT buildings are generally with 9”X9” columns and beams, less no. of

rods, higher spacing of stirrups, low strength concrete and so on

• The nonstructural cost is the main component of total cost of the building

• Structural cost vary considerably between MRT followed building and Non-

MRT building but other costs like nonstructural, service and functional remain

nearly the same in both type of buildings.

• People are investing as high rate as Rs1146.28 per Sq.ft. on their structural cost

but they are not aware of making the building safer and resilient with nearly the

same amount for following codes and standards.

• People on an average invest about RS 2600/sq.ft for construction of building

although they do not follow the MRT guidelines.

• Buildings are taken or sampled not as per location but as per building typology

and requirements of the project objectives.




19

Fig. Cost components contribution to total cost in Non-MRT buildings(per sq.ft.)

The details of estimation and rate analysis are provided in the annex of the report.

Fig. Non MRT buildings




20




21

f ig. Typical Cross sections of existing structure

3.3 COST ESTIMATION OF RETROFIT BUILDINGS

Study of non-MRT residential building has been carried out which has average plinth

area of 1000 sq.ft. These buildings seem to be vulnerable in terms of seismic activity as

compared to MRT building. Henceforth, it has been essential to re-strengthen such

building that could be possible through retrofitting. Retrofitting detail has been

considered with reference to draft report on “Seismic Retrofitting Guidelines of Buildingsin Nepal” proposed by CoRD, UNDP and MRB.




22

Fig. Plan of building (reference building for column jacketing )




23

Fig. Typical Sections of Non –MRT and Jacketed Columns




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3.4 FUNCTIONAL COST ANALYSIS

Post disaster earthquake has always created trauma and loss in different sectors.

Concerning financial loss it even covers structural, non-structural, services as well as

functional aspect of individual houses. Functional aspect covers different furniture placed

in houses. Furniture of bedrooms are estimated as per their incurred cost and numbers

whereas for kitchen cost has been estimated and the estimated cost has been considered

as standard cost in the survey. The cost of the kitchen has been estimated as follows:

Functional Cost per kitchen:

2 gas cylinders +set 15000

1 kitchen rack 10000

2 tables 6000

1 Refrigerators(owners only) 20000

1 Dining Table 20000

Kitchen Utensils 20000

Others 10,000

TOTAL 101000

Damage to such elements also adds up to financial loss. In the study this consideration

has been carried out. Since functional elements in the entire building are similar

concerning residential area of 2.5 to 3 storied so this cost has been analyzed in general.

This has been enlisted in table below:




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S.N.BLDGNOS.

BUILT-UPAREA

FUNCTIONALCOST

COST PER UNITAREA

1 B1 2077.5 823000 396.15

2 B2 2285.1 763000 333.90

3 B3 2909.64 1642300 564.434 B4 1890 755000 399.47

5 B5 2500 3584750 1433.9

6 B6 2870 1422000 495.47

7 B7 2250 1164880 517.72

8 B8 2280 1135400 497.98

AVERAGE COST PER UNIT AREA 579.88/sq.ft.

According to the survey carried out it has been found that there would be loss of Rs.579.88 per sq.ft. which will accounts into great loss at the time of earthquake.

3.5 DAMAGE GRADE ANALYSIS

For the damage grade analysis, rank has been considered as per European standard. Since

effect of damage differs in MRT followed and non-MRT buildings so based on the

ranking set by the standard, different percentage has been assigned in different

components of respective building. They are assigned as given below:

For MRT Building:


Percentage of Damage in different components

S.N. CATEGORY OF RANGE

AVG.DAMAGE

STRUCTURAL NON

SERVICES

FUNCTIONAL

DAMAGEDAMAGEINDEX INDEX

STRUCTURAL

1Minor to ModerateDamage 0-0.2 0.1 0% 20% 0% 0%

2Moderate to heavyDamage 0.2-0.6 0.4 20% 60% 40% 40%

3 Major Damage 0.6-1 0.8 60% 100% 100% 100%




26

For Non-MRT Building:


Percentage of Damage in different components

S.

N. CATEGORY OF RANGE

AVG.

DAMAGE

STRUCTUR

AL NON

SERVIC

ES

FUNCTION

AL

DAMAGEDAMAGEINDEX INDEX

STRUCTURAL

1Minor to ModerateDamage 0-0.2 0.1 20% 40% 40% 40%

2Moderate to heavyDamage 0.2-0.6 0.4 40% 60% 60% 60%

3 Major Damage 0.6-1 0.8 100% 100% 100% 100%

Based on these criteria analysis has shown following results:

DAMAGE GRADE ANALY SIS OF MRT BUILDINGS:1.Minor to Moderate Damage 2.Moderate to Heavy Damage 3. Major Damage

A.Structural Cost andDamage A. Structural Cost and Damage A. Structural Cost and Damage

% of Loss 0% % of Loss 20% % of Loss Per unit cost on average(5buildings average) 1214.23

Per unit cost on average(5buildings average) 1214.23

Per unit cost on average(5buildings average) 1

Loss per sq.ft. 0.00 Loss per sq.ft. 242.85 Loss per sq.ft. 7Built Up area (for 1 samplebuilding) 2970.00

Built Up area (for 1 samplebuilding) 2970.00

Built Up area (for 1 samplebuilding) 29

Loss Amount 0.00 Loss Amount 721253.81 Loss Amount21

B.Non Structural Cost andDamge B.

Non Structural Cost andDamge B.

Non Structural Cost andDamge

% of Loss 20% % of Loss 60% % of Loss Per unit cost on average 1474.29 Per unit cost on average 1474.29 Per unit cost on average 1




Loss Amount875728.2

6 Loss Amount 875728.26 Loss Amount43

C. Services Cost and Damage C. Services Cost and Damage C. Services Cost and Damage

% of Loss 0% % of Loss 40% % of Loss

Per unit cost on average 370.76 Per unit cost on average 370.76 Per unit cost on average 3




Loss Amount 0.00 Loss Amount 0.00 ` 11

D. Functional Cost and Damage D. Functional Cost and Damage D. Functional Cost and Damage


Per unit cost on average 548.65 Per unit cost on average 548.65 Per unit cost on average 5

Loss per sq.ft. 0.00 Loss per sq.ft. 219.46 Loss per sq.ft. 5

Built Up area 2970.00 Built Up area 2970.00 Built Up area 2

Loss Amount 0% Loss Amount 651796.20 Loss Amount16




27

Total Loss of all components875728.2

6 2248778.2748

Per sq. ft. cost 294.86 757.16 1

MRT BUILDING

CATEGORY OF STRUCTURAL NON- SERVICE FUNCTIONAL

DAMAGE STRUCTURAL DAMAGE DAMAGE

DAMAGE 1 0% 14% 0% 0%

DAMAGE 2 25% 14% 0% 29%

DAMAGE 3 75% 72% 100% 71%

Considering Structural Damage, in damage 1 category, there won’t be any loss whereas

damage 2 and 3 incur 25% and 75% loss respectively. Non-structural damage adds up

14% loss in damage 1 and 2 category whereas 72% loss is incurred in damage 3 category.

Service of the building incorporates water supply lines as well as sanitary pipe lines. This




28

system won’t get affected in damage 1 and 2 category whereas it gets affected by 100%

in damage 3 category. Similarly, functional items of the building including all the

furniture and electronic gazettes in terms of damage grade create loss of 29% and 71% in

damage 2 and 3 category.

On the other hand, non MRT building has shown following results:

DAMAGE GRADE ANALYSIS OF (CONVENTIONAL) NON MRT BUILDINGS:

1.Minor to Moderate Damage 2.Moderate to Heavy Damage 3. Major Damage

A.Structural Cost andDamage

A.

Structural Cost andDamage

A.

Structural Cost andDamage


Per unit cost onaverage(5 buildingsaverage) 901.73

Per unit cost onaverage(5 buildingsaverage) 901.73

Per unit cost onaverage(5 buildingsaverage)

901.73

Loss per sq.ft. 180.35 Loss per sq.ft. 360.69 Loss per sq.ft.901.7

3

Built Up area (for 1sample building)

2970.00


2970.00


2970.00

Loss Amount535629

.84 Loss Amount1071259.68 Loss Amount

2678149.21

B.Non Structural Costand Damge

B.

Non Structural Costand Damge

B.

Non Structural Costand Damge

% of Loss 40% % of Loss 60% % of Loss 100%

Per unit cost onaverage 1327.50 Per unit cost onaverage 1327.50 Per unit cost onaverage 1327.50



2970.00


2970.00


2970.00

Loss Amount1577074.75 Loss Amount

2365605.00 Loss Amount

3942675.00

C.

Services Cost and

Damage

C

.

Services Cost and

Damage

C

.

Services Cost and

Damage


Per unit cost onaverage 370.76


Per unit cost onaverage

370.76


6


2970.00


2970.00


2970.00




29

Loss Amount440462

.88 Loss Amount660694

.32 Loss Amount1101157.20

D.Functional Cost andDamage

D.

Functional Cost andDamage

D.

Functional Cost andDamage




Per unit cost onaverage

548.65


5

Built Up area (for1sample building)

2970.00

Built Up area (for 1sample building )

2970.00


2970.00

Loss Amount651796

.20 Loss Amount977694

.30 Loss Amount1629490.50

Total Loss of allcomponents

3204963.673

5075253.302

93514

71.906

Per Sqft 1079.11 1708.843148.6

4

NON-MRT BUILDING

CATEGORYOF

STRUCTURAL NON- SERVICE FUNCTIONAL

DAMAGE STRUCTURAL DAMAGE DAMAGE

DAMAGE 1 12% 20% 20% 20%

DAMAGE 2 25% 30% 30% 30%

DAMAGE 3 63% 50% 50% 50%




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Considering Structural Damage, there will be 13%, 25% and 63% loss in damage 1, 2 and

3 categories respectively. Non-structural damage adds up 20% loss in damage 1, 30%

loss in 2 categories whereas 50% loss is incurred in damage 3 category. Service of the

building incorporates water supply lines as well as sanitary pipe lines. This system

incurred loss of 20%, 30% and 50% respectively in 1, 2 and 3 damage category.

Similarly, functional items of the building create loss of 20%, 30% and 50% in damage 1,

2 and 3 categories respectively.

Hence, it has been found that the loss percentage of property in terms of cost differs in

MRT followed and non-MRT followed buildings. This can be clearly illustrated by

following figures




31

It has been felt that there is difference in loss in terms of cost in MRT followed buildings

and non-MRT buildings in damage 1 and damage 2 categories. On the other hand,

functional loss in both type of buildings seem to be similar. Therefore, in broader

perspective it is better to invest in MRT building rather than non-MRT in damage grade

perspective.




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CHAPTER 4

4.1 COMPARATIVE ANALYSIS




33

Benefit Cost Ratio Calculation (B/C Analysis):

A. MRT Buildings

Unit cost of construction(per/sq.ft) 3070 Benefit/Cost Ratio

1. Minor to ModerateDamage

Loss per sq.ft.(Rs) 294.86Benefit/CostRatio

Loss in Non MRT - Loss inMRT Buildings

Difference between MRT andNon MRT Cost

2.Moderate to HeavyDamage

1. Minor toModerate (1079.11-294.86)/ (3070-2600)

Loss per sq.ft.(Rs) 757.17

B/C Ratio 1.67

3. Major Damage (1708.84-757.17)/ (3070-2600)

Loss per Sq. ft.(Rs) 1647.952. Moderte toHeavy

B/C Ratio 2.02

B.Non-MRTBuildings

Unit cost of Construction 2600 (3148.65-1647.95)/ (3070-2600)

1. Minor to ModerateDamage

3. MajorDamage

Loss per sq.ft.(Rs) 1079.11 B/C Ratio 3.19

2.Moderate to HeavyDamage


3. Major Damage


From the study it has been found that initial cost required for MRT construction is more

than that of non-MRT cost. And following difference has been observed in investment:




34

Building Categories Overall Cost Structural cost

Cost/sq.ft. Cost/Sqft

MRT 3070.00 1217.25

non-MRT 2600.00 901.73Difference 470.00 315.52

Considering only the investment cost, it seems that it is beneficial to invest in non-MRT

building and this perspective is prominent in general public view and they prefer to

practice this construction. But in terms of loss caused by earthquake, scenario is found to

be different. Study showed that MRT followed buildings incurs less loss in terms of

damage caused by earthquake than non-MRT buildings. Following data obtained from

the study support the scenario:

BuildingCategories Damage Category

Minor Moderate Major

Cost/sq.ft. Cost/sq.ft. Cost/sq.ft.

MRT 294.86 757.16 1647.95

non-MRT 1079.11 1708.84 3148.65

Difference 784.25 951.68 1500.7

Furthermore, from the benefit-cost analysis following results has been found:

• For Minor to Moderate damage case: B/C ratio=1.67

• For Moderate to Heavy damage case: B/C ratio=2.02

• For Major Damage case: B/C ratio=3.19

Results suggest that,

1. B/C ratio greater than 1 suggests that the MRT building construction is beneficial

to Non MRT building techniques

2. Since B/C ratio is increasing with respect to damage grade scale, the importance

of MRT building increases with the damage grade scale




35

3. Performance level of MRT followed building is high which save high amount of

property in terms of damage and loss. Hence it can be said that it is essential to

promote building code for proper construction which not only gives proper shape

to urbanscape rather it enhance building performance that reduce the losses

created by earthquake impact.

There is no doubt that MRT followed buildings are essential but it is the fact that there

exists some non-MRT buildings on the ground which are still vulnerable. So, it is

essential to strengthen such building also. For this purpose, retrofit could be one of the

best options. According to the study, it has been found that cost required for retrofit

building is Rs.497.3/s.ft. which will again be wise step to invest to reduce the impact or

loss caused by earthquake.

4.2 CONCLUSION

In the present context of Nepal an urban environment is with high degree of proneness

and the level of preparedness is nearly negligible to earthquake. It has become a great

challenge for the mankind to reduce the impacts on lives and properties due to their

occurrences.

For stepping forward to the context and with the long range view of making disaster

resilient Kathmandu we have carried out the project work. The project work was focused

on collecting the information on cost incurred for RCC residential buildings (less than 3

storey) made with conventional technology (not following MRT standard), Earthquake

Resistant technology (MRT followed buildings) and the Retrofit technology. The total

cost was composed up of the major components like Structural, Non Structural, Service

and Functional. Each component were separately analyzed and compared to have an idea

on what amount of extra investment is necessary to follow MRT technology and retrofit

technology. With the basis of damage grade analysis for different level of earthquake

damage and loss amount in unit terms were calculated which clearly envisioned the

economic analysis i.e. B/C analysis. B/C analysis was a better proof for the urban




36

dwellers why to invest on safe and resilient techniques of construction to raise their level

of safety.

From the study it can be concluded that MRT followed buildings which has been

explained by NBC 201 is beneficial in long term vision especially in the country like

Nepal which lies in 11th position in earthquake .B/C ratio greater than 1 for all damage

case was a proof to inspire people to follow building codes. In addition to it Building

Codes are meant for people and its essence should be explained properly to them.

Furthermore, existing non-MRT buildings must be strengthened through retrofit

technology which could act as strength to the building. Henceforth, it can be concluded

that building code should be strongly implemented and importance to MRT building must

be focused because it is always better to prevent than to cure later.




37

REFERENCES

• Seismic Retrofitting Guidelines of building in Nepal (UNDP, CoRD and MRB &

Associates “Proposed Draft report”)

• NBC-201 (Mandatory Rule of Thumb-MRT)

• European Macro-seismic Scale (EMS-98)

• www.moha.gov.np

• Documents from Department of Urban Development and Building construction.

http://www.moha.gov.np/





ANNEXES

1. Detail Drawing Drafting (Architectural and Structural)

2. Detail Cost estimation

3. Rate Analysis