construction of telecommunication towers
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Construction of
Telecom Towers-Quality and Productivity
ImprovementFinal Presentation
BTP Guide: Presented By:
Prof. K N Satyanarayana N S B Syam
Dept. of Civil Engineering CE05B038
Introduction• In the next three to four years, telecom companies
(Telco's) will need another 100,000 towers and the industry estimates that at least 60 per cent of this will be built by independent operators.
• The development of the Infrastructure segment in our country is associated with many issues like poor quality, lack of safety concerns, cost overruns and project delays due to inefficient project planning and control.
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• Prominent telecom infrastructure companies -Reliance Communications, Bharti/Airtel, Vodafone, Idea Cellular, Aircel Ltd, MTNL, BSNL, VSNL etc.
• Independent telecom infrastructure companies -Tata, ATC (American Tower Corp), Indus Towers, Quippo Telecom and GTL Infra Ltd.
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Objectives• Basic study on contracting procedures, quality, cost, time,
and productivity issues in telecom tower construction industry.
• Suggesting productivity improvement methods using logistics in terms of supply chain management and process mapping of the whole construction process.
• Identifying the underlying issues and suggestions for quality in the construction of communication towers.
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Scope
• The study is limited only to address the construction related issues. Design related issues are not in the scope of the study.
• The study is limited to construction of telecom towers in and around Chennai.
• The study is focused on contracting procedures, quality problems, cost overruns, project delays in the construction of telecom towers and developing a logistics model in terms of supply chain management.
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Methodology
• Discussions with experts in telecom towers construction industry.
• Interviews of client representatives, contractor representatives and site supervisors.
• Study and analysis of data collected from the on-going projects.
• Developing a Logistics model to map the construction process in terms of the supply chain management.
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• Study required extensive site visits, to collect data from the concerned personnel and to identify the key issues prevalent in the construction of telecom towers.
• Fifteen sites were visited as a part of this project.
• Three main types of issues identified:
• Quality of the construction process
• Schedule of the construction process.
• Productivity of the construction process
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Quality Issues
Broadly classified into 7 categories based on sitedata and interviews conducted
– Material/Equipment Availability– Formwork/Reinforcement– Geotechnical Issues– Issues related to Concrete– Structural Issues– Labor Issues– Site Management Issues
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Issues Vs. No. of sites
9
Issues RTT (Total:8)
GBT(Total:7)
Material/Equipment Availability 2 3
Formwork/Reinforcement 7 7
Geotechnical Issues - 4
Concrete related Issues 8 7
Structural Issues 4 3
Labor Issues 8 7
Site Management Issues 5 7
Material/Equipment Availability
• Aggregates, Sand, Cement
• Steel for reinforcement
• Labor
• Pump for water pumping
• Vibrator for concrete
• Pulleys and bolts for tower erection
• Rubber soling to prevent seepage of water from underneath the foundation
10
Formwork/Reinforcement
• Quality of shuttering material
• Irregularity of Foundation bolts
• Leveling of formwork
• Inadequate development lengths for column extension
• Required Ld is 200mm but available length was 75mm.
• Congested Reinforcement
• Early removal of formwork
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Geotechnical Issues• Soil Investigations
• IS 6403- Code of Practice for determining Bearing Capacity of Shallow Foundation
• Sufficient number of undisturbed samples of 40-100mm ø are required for testing
• Budget for soil test on a 6mx12m site is Rs.8000
• Lack of laboratory in vicinity
• Achieving required depth for foundation• IS 1080-1985- Code of Practice foe Design and Construction of
Shallow Foundation in Soils• Min. required foundation depth is 3m
• Validity of the soil test report when compared to the actual conditions
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Concrete• Proper mix design
– IS 10262: Code of Practice for Concrete Mix Design
• Concrete cover for bolts/members– Min. cover in Chennai not less than 45mm
• Improper Maintenance/Finishing
• Segregation & Honeycombing – Honeycombing noticed in all the sites visited
• Lack of proper cube testing for checking concrete strength– IS 4031-1968 – 28 day compressive strength( Appendix C, Clause 3.8) M20
Grade– IS 9013-1978 – Accelerated curing method for determination of compressive
strength
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Structural Inadequacies –Constructability issues
• Missing Bracings/Fasteners– IS 204 (Part 1) :1991- Tower Bolts Specifications
• Movement of foundation
• Ad hock site modifications
• Template Setting
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Labor
• Poor skill of labor
• Safety rules not followed at sites– SP 70:2001 Handbook on Construction Safety Practices
• Lack of coordination among labor
26
Site Management Issues
• Supervision at sites
• Drawings/reports of tests
• Poor Handling & Storage of materials
• Accessing the site
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Scheduling Issues
Labor
Unavailability of supervisors
Timely availability of material/equipment
Weather
Holidays
No written work schedule
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Average Schedule of a 15m RTT-34 days duration
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Slowest Completed Schedule of a 15m RTT-56 days duration
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Fastest Completed Schedule of a 15m RTT-22 days duration
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Analysis of RTT schedules
• 30 days difference between slowest and fastest completed towers– Delay of 18-21 days due to material availability
– Delay of 3-4 days due to the delay between the installation of the tower equipment after the tower framework is erected
– Delay of 2-3 days is caused due to the prolonged installation period of the telecom equipment
– Delay of 2-3 days is caused in between the tower installation and the tower being on air
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Average Schedule of a 30m GBT-47 days duration
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Slowest Completed Schedule of a 30m GBT-65 days duration
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Fastest Completed Schedule of a 30m GBT-34 days duration
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Analysis of GBT schedules
• Difference of 31 days between the fastest and the slowest completed towers– Delay of 19-21 days caused due to supply of construction
material, tower material and the telecom equipment
– Delay of 2-3 days between each of the foundation levels
– Delay of 5-7 days between the installation of the tower and the completion of the tower foundation
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Process Mapping
1. What is Process Mapping?
2. Why are we applying Process Mapping?
3. How is it useful in this project?
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Process Mapping is a powerful tool that offers an in-depth
understanding of any given process, finds effective ways for that
process to be more successful, and ensures that true value is
being provided to the client/customer.
There are four major steps of Process Mapping– Process identification – attaining a full understanding of all the steps
of a process.
– Information gathering – identifying objectives, risks and key controls in a process.
– Interviewing and mapping – understanding the point of view of individuals in the process and designing actual maps.
– Analysis – utilizing tools and approaches to make the process run more effectively and efficiently.
Back
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• Process Mapping is used in this project to identify the different processes that constitute the telecom tower construction.
• Helps in increasing the productivity of the overall process by focusing on the processes that need rework for their improvement.
• Telecom tower construction consists of a lot of processes ranging from Radio Frequency survey to the handing over of the completed tower on air.
• It allows all the individuals working on the project to gain a better understanding of that process with a simple, yet powerful approach that anyone can utilize.
Back
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Process Identification
Worksheet
Area of business being reviewed: Telecom tower construction
Trigger Events Process Name
Growth of mobile phone users in the country. Need for better networking and
hence construction of telecom towers. Survey done to locate the right
locations for the tower constructions.
RF Survey
Optimal location of tower site for better reach of customers. Site Identification/ Land
Acquisition
Drawings for the construction of towers. Layout Plans
Type of foundation needed for GBTs for the construction. The structural
stability of the existing structure for RTTs.
Soil Investigation/
Structural Stability
Protection and to prevent trespassing and misuse of the tower, fencing and
guard room to be constructed. Safety and protection of tower.
Fencing, Compound wall,
Guard Room, DG Slab,
Shelter Foundation
Construction materials like, steel, sand, cement, aggregates for the tower
foundation construction, tower fabrication set for tower material and
equipment like vibrator, pulleys for tower erection.
Tower Supply & Erection
Diesel Generator set installation which is the key component of the tower
construction.
DG set installation
Shelter for the security guard and to store maintenance parts for emergency
replacement of parts of the tower.
Shelter Supply & Erection
Earthing to prevent damage by lighting and electrical works in order to ensure
proper functioning of the antennae.
Electrical- Indoor, Outdoor
and Earthing
Backup power options for the transmission of signals. AC installation, Battery,
PIU
Need for a base station to receive and transmit signals. Installation of BTS
Need for the transmission of signals. Antennae Installation
Connections of antennae to the electrical systems for proper functioning of the
system.
RF Cable Routing
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Comprehensive Business Time Line Worksheet
Telecom Tower ConstructionC
ivil W
ork
sC
ivil W
ork
sE
lectr
ica
l &
Me
ch
an
ica
l
Wo
rks
Ele
ctr
ica
l &
Me
ch
an
ica
l
Wo
rks
Te
leco
m W
ork
sT
ele
co
m W
ork
sS
urv
eyin
gS
urv
eyin
g
RF SurveyRF Survey Site Identification/Land
Acquisition
Site Identification/Land
Acquisition
Layout PlansLayout Plans Soil Investigation/Structural Stability
Analysis
Soil Investigation/Structural Stability
AnalysisFencing/Compound Wall, DG Slab, Shelter
Foundation
Fencing/Compound Wall, DG Slab, Shelter
Foundation
Tower Supply &
Erection
Tower Supply &
ErectionElectrical- Indoor, Outdoor and
Earthing
Electrical- Indoor, Outdoor and
EarthingShelter Supply &
Erection
Shelter Supply &
Erection
AC Installation,
Battery, PIU
AC Installation,
Battery, PIUInstallation of
BTS
Installation of
BTSAntennae
Installation
Antennae
InstallationRF Cable
Routing
RF Cable
RoutingWi-max
Installation
Wi-max
Installation
Tender 1-
Company CTender 2- Company D
Tender 3 – Company A
Tender 3 – Company A
Tender 4 – OEMs – Company B
Tower
Foundation
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Process Profile Worksheet
Process Name and Number
RF survey : 1
Process Owner
Principal Companies/Telecom Companies
Description :
The ultimate goal of a RF site survey is to supply enough information to determine the number and
placement of access points that provides adequate coverage throughout the facility. In most
implementations, "adequate coverage" means support of a minimum data rate. A RF site survey also
detects the presence of interference coming from other sources that could degrade the performance of the
wireless LAN.
Triggers
Event Beginning: Call for tenders for RF surveying.
Event Ending Process: Document findings of the sites best suitable for telecom tower construction.
Additional Events: Call for tenders for more than 1 company to save time. For 100 sites to be RF
surveyed, 10 companies could finish the survey in 10 times less time than the survey being done by a
single company.
Inputs – Items and Sources
Surveying equipment like Theodolite, GPS, Satellites
Outputs – Items and Sources
Optimal location of sites for the construction of telecom towers
Process Units
Obtain a site facility diagram
Visually inspect the site facility
Identify cellular phone user areas
Determine preliminary site access point locations
Verify site access point
Process Unit Owners
Telecommunication Companies
Business Objectives
Location of sites which offer better transmission
of signals and networking
Business Risks
Time consuming and tiring process. A slight change
in the site location may not yield transmission signals.
Accuracy is very important.
Key Controls
Skilled usage of GPS systems and accuracy of
the instruments.
Measure of Success
Best fit site which can ideally transmit and receive
signals with maximum efficiency. 42
Tower Construction
Initiation
RF survey
Obtain an area
facility diagram
Visually
inspect
the
facility
area
Identify
cellular
phone
user
areas
Determine
preliminary access
point locations
Verify
access
points
Site Identification/
Land Acquisition
Negotiations with
the owner
Successful
Negotiation
Land acquired for
tower construction
Layout Plans
Type of Tower
Soil Investigation
Structural Stability
Analysis
Common Civil
works
Guard
Room
foundation
Fencing
Superstructure
of the guard
room
Tower and Shelter
Material Supply
Formwork and
Reinforcement
Concreting
Tower
and
Shelter
Erection
Yes
No
GBT
RTT
DG set
A
43
Electrical
Indoor Outdoor
Installation
of RBS
Fixing of
cable
ladder
Installation
of rectifier
and battery
bank
Routing
of
cables
Clamping
Ground/
Earthing
Telecom
Installations
Antennae
Installation
GSM Microwave
Installation
of PIU,
power
backup
Site on air
A
44
Suggestions• Prior stacking of materials at the job site
• Adequate supervision
• More labor compared to peak labor requirement
• Use of process charts and work schedules
• Safety equipment
• Use of vibrator and other equipment to prevent segregation and honeycombing
• Use of system formwork
• Grouting of bolts
• Leveling of beams, columns and template settings
• Centralized warehouse catering the needs of each construction site
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References
• Dileep R. S, 2001, Logistics of Facility Location and Allocation, United States of America, Marcel Dekker, Inc.
• Jacka, M J., 2002, Business Process Mapping, United States of America, John Wiley & Sons, Inc.
• LakshmiNag P (2006), Productivity Issues in Construction of Steel Communication Towers, Bachelor of Technology Thesis,
Indian Institute of Technology Madras, Chennai
• Kumar S, 2006-Types and Design of Steel Towers, Structural Steel Design, Indian Institute of Technology, Madras,
http://nptel.iitm.ac.in/courses/IIT-MADRAS/Design_Steel_Structures_II, (accessed May 2006)
• IS 204 Part 2 :1992 – Tower Bolts Specifications
• IS 456 (2000) – Plain and Reinforced Concrete-Code of Practice
• IS 800 (2007) - General Construction in Steel–Code of Practice
• IS 802 (Part 1/Sec 2): 1992 – Use of Structural Steel in Overhead Transmission Line Towers- Code of Practice
• IS 806: 1988 - Code of Practice for use of Steel Tubes in General Building Construction
• IS 10262 – Recommended Guidelines for Concrete Mix Design
• IS 875 Part 3: 1987 – Code of Practice for Design Loads for Buildings and Structures
• IS 4091-1979 – Code of Practice for Design and Construction of Transmission Lines and Poles
• Chetan, 2007, Civil Construction Issues, Proceedings of workshop conducted for M/s GTL Infra Ltd., Indian Institute of
Techology Madras, Chennai, Nov 3rd 2007
• Gandhi S R, 2007, Geotechnical Issues related to Telecommunication Tower Construction, Proceedings of workshop
conducted for M/s GTL Infra Ltd., Indian Institute of Techology Madras, Chennai, Nov 3rd 2007
46
• Gettu R, 2007, Concrete Properties, Proceedings of workshop conducted for M/s GTL Infra Ltd., Indian Institute of
Techology Madras, Chennai, Nov 2nd 2007
• Kalyanraman, 2007, A Review of Steel Tower Skeleton System, Proceedings of workshop conducted for M/s GTL Infra Ltd.,
Indian Institute of Techology Madras, Chennai, Nov 3rd 2007
• Menon, 2007, Fixing of Ground Based and Roof Top Towers-Structural Issues, Proceedings of workshop conducted for M/s
GTL Infra Ltd., Indian Institute of Techology Madras, Chennai, Nov 2nd 2007
• Advantages and disadvantages of tubular and angular towers, http://www.monsterfm.com/tech/tower/towerspecs.htm#top
(accessed April 2009)
• Estimate of Cell sites construction 2007, http://www.airtel.in/wps/wcm/connect/ (accessed January 2009)
• Indian Telecom Sector Analysis (2006-2007), http://www.rncos.com/Report/IM073.htm (accessed November 2008)
• ITU World Telecommunication base indicator 2007, www.itu.int (accessed October,2008)
• Site Installation, http://www.topcomco.com/civil_work.htm (accessed March 2009)
• Site Survey, http://www.topcomco.com/site_survey.htm (accessed January 2009)
• Structural changes in the Indian Steel Industry 2003, http://jpcindiansteel.nic.in/structure.asp (accessed December 2008)
• Tower design specifications, http://www.rajessh.com/towerdesignspecifications (accessed February 2009)
• Tower materials, http://www.topcomco.com/ti.htm (accessed April 2009)
• Tower specifications, http://www.monsterfm.com/tech/tower/towerspecs.htm (accessed January 2009)
• Why cell tower business is booming?, www.financialexpress.com/news/whys-cell-tower-business-booming/407427/
(accessed April 2009)
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THANK YOU
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