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Construction of Telecom Towers- Quality and Productivity Improvement Final Presentation BTP Guide: Presented By: Prof. K N Satyanarayana N S B Syam Dept. of Civil Engineering CE05B038

Construction of telecommunication towers

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Page 1: Construction of telecommunication towers

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

Page 2: Construction of telecommunication towers

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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Page 3: Construction of telecommunication towers

• 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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Page 4: Construction of telecommunication towers

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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Page 5: Construction of telecommunication towers

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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Page 6: Construction of telecommunication towers

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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Page 7: Construction of telecommunication towers

• 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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Page 8: Construction of telecommunication towers

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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Page 9: Construction of telecommunication towers

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

Page 10: Construction of telecommunication towers

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

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Page 11: Construction of telecommunication towers

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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Page 17: Construction of telecommunication towers

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Page 18: Construction of telecommunication towers

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

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Page 27: Construction of telecommunication towers

Site Management Issues

• Supervision at sites

• Drawings/reports of tests

• Poor Handling & Storage of materials

• Accessing the site

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Page 28: Construction of telecommunication towers

Scheduling Issues

Labor

Unavailability of supervisors

Timely availability of material/equipment

Weather

Holidays

No written work schedule

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Page 29: Construction of telecommunication towers

Average Schedule of a 15m RTT-34 days duration

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Page 30: Construction of telecommunication towers

Slowest Completed Schedule of a 15m RTT-56 days duration

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Page 31: Construction of telecommunication towers

Fastest Completed Schedule of a 15m RTT-22 days duration

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Page 32: Construction of telecommunication towers

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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Page 33: Construction of telecommunication towers

Average Schedule of a 30m GBT-47 days duration

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Page 34: Construction of telecommunication towers

Slowest Completed Schedule of a 30m GBT-65 days duration

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Page 35: Construction of telecommunication towers

Fastest Completed Schedule of a 30m GBT-34 days duration

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Page 36: Construction of telecommunication towers

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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Page 37: Construction of telecommunication towers

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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Page 38: Construction of telecommunication towers

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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Page 39: Construction of telecommunication towers

• 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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Page 40: Construction of telecommunication towers

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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Page 41: Construction of telecommunication towers

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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Page 42: Construction of telecommunication towers

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

Page 43: Construction of telecommunication towers

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

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Page 44: Construction of telecommunication towers

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

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Page 45: Construction of telecommunication towers

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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Page 46: Construction of telecommunication towers

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

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Page 47: Construction of telecommunication towers

• 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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