Summer Training Siddharth Srivastava A2315813131(1)
Final Project
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SUMMER INTERNSHIP REPORT
(23/06/2016 – 22/07/2016)
KCC Institute of Technology & Management
Knowledge Park-III, Greater Noida-201306(UP)
SUBMITTED BY:
NAVEEN KUMAR
Roll No. - 1349200033
(Final Year Civil Engineering Student)
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TABLE OF CONTENTS
S. No. Content Page No.
1 Approval Certificate 3
2 Acknowledgement 4
3 Declaration 5
4 Introduction 6
5 Project Brief 10
6 EHS Department 11
7 QA/QC Department 15
8 Project Execution 19
9 Construction of Methodology 25
10 Reinforcement of segment 27
11 Method of statement 29
12 Information about equipment 30
13 Safety measure & Campaign 33
14 Some Important notes 35
15 Conclusion 36
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APPROVAL CERTIFICATE
The following study is hereby approved as creditable for the training purpose, carried out and
presented in a manner sufficiently satisfactory to warrant its acceptance.
It is to be understood that by this approval the undersigned does not necessarily endorse or approve
any statement made, opinion expressed or conclusion drawn there in, but approve the study only for
the purpose for which it is submitted.
This project report entitled “Construction of Larsen &Toubro Construction” by Naveen Kumar is
approved for the degree of Bachelor of Technology in Civil Engineering.
Trainee: Naveen Kumar ( )
Project Director: Mr. Shubhendu Bose ( )
Date:
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ACKNOWLEDGEMENT
A summer project is a golden opportunity for learning and self-development. I consider myself very
lucky and honoured to have so many wonderful people lead me through in completion of this
project.
I am highly indebted to KCC Institute of Technology & Management (GreaterNoida) for their
guidance and constant supervision as well as for providing necessary information regarding the
project & also for their support in completing the project. I would like to thank my advisor and
faculty guide for the valuable inputs he has provided during the development of the engineering
project, who took time out to instill intellectual advice and strode me through the right path. I would
also like to thank Mr. Deepak Gupta (Chairman) for serving on the civil department and going
through my work, in spite of a busy schedule.
I am very thankful to LARSEN & TOUBRO LIMITED CONSTRUCTIONS for having given me the
opportunity to undertake my summer training at their prestigious BARAPULLAH OVER HANGIGNG
BRIDGE PROJECT SARAI KALE KHAN TO MAYUR VIHAR PHASE-I. It was a very good learning
experience for me to have worked at this site as this project involved many unique construction
practices and challenges. I would like to convey my heartiest thanks to Mr. Shubhendu Bose (Project
Manager) who heartily welcomed me for the internship. I would also like to give my heartiest thanks
to Mr. Banerji Sir (Planning Manager), and Mr. Mahender Singh (QA/QC Incharge) who guided and
encouraged me all through the summer training and imparted in depth knowledge of the project.
Also I would like to thank Mr. Nitesh Kumar (Site Engineer) who assisted and guided me whenever I
needed help. I would like to thank all the department heads of L&T Construction, B&F, and IC for
giving their precious time and valuable guidance during my internship programme.
Last but not the least, I would like to thanks all the staff at L&T Constructions, B&F, IC for being so
helpful during the summer training.
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DECLARATION
This is to certify that I, Naveen Kumar student of B.Tech (Civil) - 6th Semester University Roll No.
1349200033 has undergone industrial training in "L & T Construction " as required of 30 days
project semester for the award of degree of B.Tech. Civil Engineering “KCC Institute of Technology
and Management ” , Greater Noida (UP) and prepared the report entitled Construction of L&T
Construction, NEW DELHI which is an authentic record of my work carried out at Sarai Kale
Khan,Opposite to Indraprastha Park, New Delhi.
If any discrepancy is found regarding the originality of this project I may be held responsible. I have
not copied from any report submitted earlier this or any other university. This is purely original and
authentic work.
Date Name of Student Signature
…………………….. …………………….. ………………….
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INTRODUCTION
ABOUTTHE ORGANISATION:-
Larsen & Toubro is the biggest legacy of two Danish Engineers, who built a world- class organization
that is professionally managed and a leader in India’s engineering and construction industry. It was
the business of cement that brought the young Henning Holck-Larsen and S.K. Toubro into India.
They arrived on Indian shores as representatives of the Danish Engineering firm F L Smidth & Co in
connection with the merger of cement companies that later grouped into the Associated Cement
Companies.
L&T Construction has played a prominent role in India’s industrial and infrastructure development by
executing several projects across length and breadth of the country and abroad. For case of
operations and better operation management, in-depth technology and business development as
well as to focus attention on domestic and international project execution, entire operation of L&T
Construction is structured into different independent companies.
Hydrocarbon IC
Infrastructure IC
Metallurgical & Material Handling IC
Power Transmission and Distribution
Heavy Engineering
Ship-Building
Power
Electrical and Automation
Material & Industrial Product
ECC today is organized in to Three Operating Companies and One Independent Company to allow for
more in-depth technology and business development as well as to focus attention on domestic and
international project execution. Each Operating Company is further split into different Business Units
(BUs) to take care of the specific needs of various customers. The Operating Companies (OC)
includes:
Infrastructure (Infra OC)
Metallurgical, Material Handling & Water (MMH &W OC)
Electrical & Gulf Projects (E&GP OC)
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QUALITY POLICY:-
At L&T, environment, health & safety (EHS) is given the highest priority. The EHS policy enunciated by
the corporate management lays emphasis on Environment, Health and Safety through a structured
approach and well defined practices. Systems and procedures have been established for
implementing the requisites at all stages of construction and they are accredited to the International
standards of ISO 9001:2008, ISO 14001:2004 and OHSAS 18001:2007.
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WORK CULTURE:-
Work culture emphasizes:
1. Freedom to experiment
2. Continuous learning and training and Transparency
3. Rewards based on performance and potential
4. Quality in all aspects of work
TRAINING:-
Human resources department believes that quality is the hallmark of any successful venture. Quality
training and development of human resources is realized through: Identifying training needs within
the Organization and designing and implementing those needs based training programs to bring
about continuous up-gradation of knowledge, skills and employee attitudes.
VISION & MISSION:-
Vision:-
L&T shall be professionally managed Indian multinational committed to total customer satisfaction
and enhancing shareholder value. L&T shall be an innovative entrepreneurial and empowered team
constantly creating value and attaining global benchmarks. L&T shall foster a culture of caring trust
and continuous learning while meeting expectations of employees, stakeholders and society.
Mission:-
To achieve excellence in the field of Engineering, Procurement and Construction through world class
practice and standards in quality, safety and project management.
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PROJECT
BARAPULLAH OVER HANGIGNG BRIDGE
(SARAI KALEKHAN TO MAYUR VIHAR PHASE-I)
PROJECT BRIEF:-
Project Parameters Details
Project Name : Barapullah Over Hanging Bridge
Client : Public Work Department (PWD)
Agency : Larsen & Toubro Ltd. (L&T)
Third Party Inspection : Rites Limited
Quality Assurance : Rites Limited
Structural Consultant : Tandon Consultant Pvt. Ltd.
Proof Structural Consultant : Aecom Asia Co. Ltd.
Project Value : Rs. 964.00 Crore
Administrative Approval : Rs. 1260.63 Crore
Date of Start : 28/04/2015
Date of completion : 27/10/2017
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BRIEF INTRODUCTION OF PROJECT:
Infrastructure major Larsen & Toubro today said its construction arm had won orders worths Rs.2101
crore across various business segments in March this year.
The Project will connect Sarai Kale Khan and Mayur Vihar through the elevated corridor across river
Yamuna. The scope includes construction of a 550m,6-lane extra dosed bridge and a 4.3 km,4-lane
elevated road, a flyover at Mayur Vihar side ,connecting loops, cycle tracks, road works etc.
It is expected that the entire Barapullah corridor will carry around 1,50,000 vehicles by 2020.
The release said the company water and renewable energy business had secured an order worth Rs
267 Crore from Uttar Pradesh Jal Nigam for the construction of 242km waste water network and
three waste water pumping station in Allahabad.
The project will connect Sarai Kale Khan and Mayur Vihar through the elevated corridor across river
Yamuna. The scope includes construction of a 550m, 6-lane extra dosed bridge and a 4.3km, 4-lane
elevated road, a flyover at Mayur Vihar side, connecting loops, cycle tracks, road works, architectural
lighting and other allied works.
EHS DEPARTMENT
Project EHS plan objective:-
1. To determine broad parameters of HSE management at site.
2. Establish & define line of command for resolution of all hazard prevention issues.
3. Define individual responsibilities hazard prevention & safety promotion responsibility at each level
of the construction team.
4. Identify highly hazardous operations within the scope of work and specify integrated preventive
measures to mitigate the same.
5. To ensure compliance with relevant applicable legislation.
6. Continual HSE performance improvement by directing focus on the key areas for improvement in a
consistent manner.
General EHS Rules & Regulations at site:-
The followings are the general EHS Rules & Regulations adopted in the site areas:
Use of Personal protective Equipment and safety devices relevant to site activities.
General housekeeping, stacking of materials.
Road safety inside project.
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Access, Egress & workstation safety.
Safe use of construction power supply and upkeep / maintenance of installations.
Use, maintenance & Inspection of Plant & Machinery.
Scaffold & Formwork norms.
Use of safe material & personnel handling devices as per requirement.
Fire prevention, protection & preparedness.
Safety Walk down involving all section heads. Points discussed are being reviewed in the daily
progress meeting and checked for compliance in the next walk down
Safety signboards and posters in Hind/English are being placed at various locations in the
site.
All legal compliances are according to BOCW 1996, Tamil Nadu for the maintenance of health
safety and environment at construction site.
EHS orientationtraining of workmen:-
The workers reporting at site are given safety induction by the Safety In-charge, wherein they talk
about the importance of safety giving emphasis to the family behind the workers and motivating
them to follow safe practices. They Emphasis on:
Overview of site
Falls
Earth work
Electricity
Machinery
Handling materials
Housekeeping
Fire
PPE – Availability & usage
Health – Site welfare facilities & potential health hazards
The workers are being shown a video on a television set and are asked to raise queries if they have
any and then workers are sent to relative working areas. Video module for every new working person
in site induction training is compulsory. Continuous display of EHS Awareness Videos/Presentations
in LCD TV in canteen area during Tea/Lunch break & TV in Main Entrance of the site.
Use of Personal protective equipment and safety devices relevant to site
activities:-
1. SAFETY APPLIANCES:-The requirement of sufficient number of safety appliances (Reflective
jackets) are planned well in advance and made available at stores.
2. HEAD PROTECTION:-Every individual entering the site must wear safety helmet, confirming to
IS: 2925-1984 with the chinstrap fixed to the chin.
3. FOOT AND LEF PROTECTION:-Safety footwear with steel toe is essential on site to prevent
crush injuries to our toes and injury due to striking against the object.
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4. HEARING PROTECTION:-Excessive noise causes damage to the inner ear and permanent loss
of hearing. To protect ears use ear plugs/ear stuff as suitable.
5. EYE PROTECTION:-Person carrying out grinding works, operating pavement breakers and those
involved in welding and cutting works should wear safety goggles and face shields suitably. Goggles,
Safety spectacles, Face shields confirm to IS: 5983-1980.
6. EAR PROTECTION:-Ear muff/ear plug should be provided to those working at places with high
sound levels (confirm to IS: 9167-1979).
7. HAND AND ARM PROTECTION:- While handling cement and concrete & while carrying out
hot works like gas cutting, grinding and welding usage of hand gloves is a must to protect the hand,
Cotton gloves (for material handling) - IS: 6994-1973.
Rubber gloves- 18 inch (380/450mm long), Electrical grade (tested to 15000 volts) confirming
to IS: 4770-1991.
Leather gloves- Hot works/handling of sharp edges.
8. RESPIRATORY PROTECTION:-Required respiratory protection according to the exposure of
hazards to be provided.
9. SAFETY NETS:- Though it is mandatory to wear safety harness while working at height on the
working platforms, safety nets of suitable meshsize shall be provided to arrest the falling of person
and material on need basis generally of size (6m* 3m) and bearing capacity of 100 Kg/sq-meter.
10. FALL PROTECTION:-To prevent fall of person while working at height, personal engaged more
than 2 meter wear standard full body harness should be confirming to IS:3521-1999 (Third Revision).
Land yard should be of 12mm poly-propylene rope and of length not more than
2 meter.
Double Land yard based on the requirement.
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Good Practices at Sites: Safety department of the sites is very active and with the help of
supervisors the safety is maintained in site:
24 hour ambulance at site
Emergency assembly point
First Aid room
Posters
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QA/QC DEPARTMENT
Quality is the key component which propels performance and defines leadership traits. At L&T
construction, quality standards have been internalized and documented in quality assurance
manuals. L&T construction recognizes the crucial significance of the human element in insuring
quality. Structured training programme ensures that every L&T employee is conscious of his/her role
and responsibility in extending L&T construction’s tradition of leadership through quality. A
commitment to safety springs, concern for the individual worker “Every one of the thousands braving
the rigours of construction at numerous project sites.” L&T, Building and Factories, IC has a well
established and a documented Quality Management System (QMS) and is taking appropriate steps to
improve its effectiveness in accordance with the requirements of ISO: 9001-2008. Relevant
procedures established clearly specify the criteria and methods for effective operation, control and
necessary resources and information to support the operation and monitoring and these processes.
Project quality plan& quality management system:-
L&T-ECCD at ESIC, Coimbatore site has a well-established and documented Quality Management
System (QMS) as per the requirements of ISO 9001:2009. Relevant procedures have been established
which clearly specify the criteria and method for effective operation, control and necessary resources
and information to support the operation and monitoring of these processes. There are procedures
for implementing, monitoring, measuring and analyzing the processes so that necessary action can
be taken to achieve the desired results, and continuously improve these processes. The Project
Quality Plan comprises of three sections:
Volume 1:
ISO Manual: It is the quality manual of ECC division. It constitutes sections, which give information
about management responsibility, resource management, and quality management system.
Volume 2:
Work Procedures: Work procedures for all civil, mechanical, electrical, structural activities are
described in detail in the work procedure section.
InspectionTest Plan: Inspection Test Plan provides information related to testing and inspection
to be conducted on various activities. There is a checklist of inspections to be done on various
activities. The ITP for an activity comprises the activity name, nature of check/inspection, method of
check, frequency of check, reference procedure/check, and format for record, inspection authority
name, and remarks.
Project Quality Check: Sampling approach is used for measuring construction work against
specification. The responsibility of Quality checks rests on auditor and the quality control engineer.
The project quality check gives the sampling criteria, the area of check, and nature of check and
maximum points that can be given to each sub-check.
Volume 3:
Formats:As the name suggests these are formats, which need to be filled in after a specific test is
over e.g. test report for aggregate it gives the list of test conducted, date of test, its results and
remarks.
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Responsibilitiesof official at Site:-
Handle Staff for inspection and tests of materials and workmanship.
Correspondence with client through reports and resolve complaints.
In charge of Non-conforming product, preventive and corrective actions to be taken and risk
register to be maintained.
Train employees, sub-contractors, supervisors and workmen for quality control and marking is
done after training to see if they are suitable to maintain quality of work.
1. Grade A (75% above) - Pass
2. Grade B (60% to 75%) - Briefing Needed
3. Grade C (below 60%) - Briefing and Training Needed
Maintain paper work like: Monthly quality report, Work completion report, Cost of poor
quality etc.
Handle and inspect materials in store.
Give product quality rating.
Maintain availability of latest drawings and also ensure that only latest drawings are being
used at site for construction purpose.
Report top management for coordinated project management.
Control and check the monitoring & measuring equipment.
Handle the quality of purchased items.
One of the biggest responsibilities is toconduct various tests. Some of them
observedby me during training were:
CompressionCube Test: To check achieved strength of concrete in 7 & 28 days. Cube
tests for M25 and M50 concrete were observed.
Concrete SlumpCone Test: To check workability of concrete mix. Ideal slump should be
125 mm. Variation of 25 mm on both sides is permitted.
Sieve Tests:
a. Cement- No more than 10% of material should be greater than 90 Micron.
b. Fly ash- No more than 10% of material should be greater than 45 Micron.
Sand Gradation Test: Grade 1,2,3,4 (1 being most course and 4 being finest, Usually 2 or
3 grades are used due to easy availability. Courser the sand better it is for purpose of making
concrete mix. Preferably Grade-2 used for Concrete and Grade-3 used for Plastering).
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VARIOUS TESTS ON MATERIALS:
1. TEST ON CEMENT
Consistency
Initial Setting time
Final Setting time
2. TEST ON AGGREGATES
Sieve Analysis
Water absorption
3. TEST ON FRESH CONCRETE
Slump test
4. TEST ON DETERMINETHE MIX DESIGN
To find the target mean strength
Determine water/cement ratio
Determine cement content
BATCHING PLANT
I also got an opportunity to visit Batching Plant and saw a sample concrete test done before major
production. Batching plant consists of Silos (100 ton capacity) to hold cement and fly ash. Cement
pump, pumps cement to pan mixer while sand and aggregate reaches pan mixer through a conveyer
belt after being measured for quantity through a bucket system. This mix is added with water and
admixtures in the pan mixer and finally the mixing starts. The resultant design mix is released in the
TM which is transferred to site for pouring through pumps, boom placer etc. Capacity of a TM is 6 cu
m and RMC should be poured within 2 hrs of production.
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PROJECT EXECUTION
Execution is one of the most important factors for the proper functioning and safety of the structure.
Negligence in this department can have devastating effects on structural stability as well as safety of
people. It reflects the combined effort of all the other departments in a construction site Execution
mainly comprises of the following things:
Survey
Reinforcement
Formwork
Concreting
Finishing
SURVEY: Survey is the first step done in any construction site so as to get:
1. The required level of the surface.
2. Check the thickness of slab during shuttering.
3. Column Layout
Survey on this site is carried out by SOKKIA (total station).
REINFORCEMENT:Reinforcement plays very important role in the construction of framed
structures and here in this project it comprises of TMT steel (Fe-500) and structural steel members.
The TMT steel bars are available in different diameters and used as per the structural design. The
various diameters available in the market are: 8mm, 10mm, 12mm, 16mm, 20mm, 25mm, 28mm and
32 mm. The weight of the steel members is measured as per running meters depending on diameter
of the rod. Weight of rebar per meter with a diameter ‘D’ is D2/162 …Kg/m.
Structural members are of two types:
1. Compression member
2. Tension member
Compression Members Ex: Column, Walls etc. Tension Members Ex: Beam, Slab etc.
Stirrups:When tying up the stirrups to the main reinforcements, the bend maintained should be
depended on the diameter of bars. Bars having diameter below 25 mm the bend length is 1d and
above 25 mm is 2d. Where’d’ is the diameter of the rod.
Rolling margin: The difference between the actual weight and the theoretical weight is the rolling
margin. This is the profit or loss deciding factor in the case of steel. The calculation of rolling Marginof
steel rebar per meter length: Theoretical weight for 8 mm diameter rebar = (d2/162) = 0.395
kg/meter length.
Then, Rolling margin = Actual Wt. - TheoreticalWt. = 0.402-0.395 = 0.07 Kg……….. (Actual wt.
assumed)
Actual Weight:It is the actual weight of rebar per meter measured. By random sampling rebar is
selected from a lot and is made cut exactly at one meter with fine finishing’s at the edges and then
weigh the rod to determine the weight. In the above calculation actual weight of rebar is assumed.
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In a project, if client pays bill in terms of weight for the steel; then rolling margin plays very
important role. Then there are two important parameters which decide internal profit or loss for
contractor.
1. If difference between the actual weights to theoretical weight is ‘positive’, then no internal
profit for the contractor.
2. If the difference is „negative‟, then contractor earns the internal profit.
Reconciliationof reinforcement:
Received = Stock Available at yard + Claimed + Wastage
Responsibility of sectionincharge:Reinforcement section is separate in this project, where in
the incharge is having the responsibility as follows:
Procurement of material
Preparation the Bar bending schedule (BBS) for the reinforcements that they are going
tie at site.
Supply of reinforcement at site.
Client approval for rebar material.
Subcontractor labour allocation.
Preparation of bill.
Rebar reconciliation.
Controlling wastage of material according to ACE value.
The Reinforcement department is one of the crucial departments at site. This department
coordinates with the entire tower to meet their requirement of reinforcement and concerned
drawings. During my training i got an exposure of the following operation:
Preparation of bar bending schedule.
Cross check for any missing details (i.e. denominations, spacing, no. of bars etc.) in detailed
drawing with Mother Drawing and good for construction drawings.
Study and understand drawings.
RC Cad for detailing and BBS preparation.
Methodfor reinforcement work:
1. All reinforcement (R/F) shall be placed above the ground by using wooden sleepers or concrete
blocks.
2. For reinforcement, care shall be taken to protect the R/F from exposure to saline atmosphere
during storage, fabrication and use.
3. Against requirement from site, bars shall be cut and bent to shape and dimension as shown in bar
bending schedule based on Good for Construction (GFC) drawings.
4. R/F shall be tied as per the latest GFC drawing and any extra bars provided at site shall be recorded
in the pour card/ lap register.
5. Unusable cut rods and scrap R/F shall be properly placed at yard.
BAR BENDING SCHEDULE
1. Prepare BBS based on the latest GFC drawing and to be submitted to engineer to review.
2. BBS shall clearly specify the following:
a) Bar diameter
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b) Numbers
c) Cut-lengths
d) Shapes
3. BBS shall take into account the following field/ design requirement.
a) Desirable lap locations and staggering of laps
b) Lap lengths
c) Development length/ Anchorage length
Cutting, Bending andPlacing Of Bars:
1. All R/F shall be free from loose mill scales, loose rust and coats of paints, oils, mud or any other
substances which may destroy or reduce bon. Use wire brush to clean the R/F.
2. Cutting and bending shall conform to the details given in the approved BBS schedule.
a) Cutting of rebar is not permitted, only cutting by grinding or shearing is permitted.
b) No heating is allowed to felicitate bending of rebar.
3. Place the R/F as per GFC drawings ensuring the following aspects properly.
a) Type & size of bars
b) Numbers of bars
c) Location and length of laps, splices
d) Curtailment of bars
e) In two way R/F, check the direction of R/F in various layers
f) Adequate number of chairs, spacer bars and cover blocks
g) Size of cover blocks
h) All the bars shall be tied with double fold 18 gram soft GI annealed binding wire.
4. Reinforcement may be placed with following tolerance whenever required:
a) For effective depth of 200 mm or less +/- 10 mm
b) For effective depth more than 200 mm +/- 15 mm
c) The cover shall in no case be reduced by more than one third of the specified cover or +/-
10 mm
d) The cover should suit various cover requirements as per drawing notes
5. The sequence of R/F shall be correlated with fixing of inserts, sleeves, conduits, anchors and
formworks.
6. In walls, place accurately bent spacer bars wired to vertical or horizontal bars between successive
rows.
7. No steel parts of spacers should allow inside the concrete cover. Spacer blocks made from cement,
sand and small aggregate shall match the mix proportion of the surrounding concrete. Alternatively
PVC cover blocks of approved make can be used.
8. Spacers, cover blocks should be concrete of same strength or PVC.
9. Spacers, chairs and other supports detailed on drawings, together with such other supports as may
be necessary, should be used to maintain the specified nominal cover to the steel R/F.
10. Spacers or chairs should be placed at a maximum spacing of 1 meter and closer spacing may
sometime be necessary.
11. All reinforcement shall be placed and maintained in the positions shown in the drawing by
providing proper cover blocks, spacers and supporting bars.
12. Rough handling, shock loading (prior to embedment) and the dropping of R/F from a height
should be avoided. Reinforcement should be secured against displacement.
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CONCRETING:For design mix concrete, the mix shall be designed to provide the grade of concrete
having the required strength, workability & durability requirements given in IS; 456-2000 for each
grade of concrete taking into account the type of cement, minimum cement content and maximum
w/c ratio confirming to exposure conditions as per tender specifications.
No concreting shall be done without the approval of Client & Engineer. Prior notice shall be given
carried out as per IS: 456-2000.
During hot and cold weather, suitable methods to reduce the loss of water by evaporation in hot
weather and heat loss in cold weather will be adopted as per procedure set out in IS: 7861.
The focus of this monograph is the chemistry, microstructure, and properties of cement and
concrete, not the nuts and bolts of how to mix and pour the stuff. However, the majority of concrete
is mixed and put into its final form in one continuous process, in contrast to materials like steel which
are manufactured first and then assembled later (some concrete, called "precast concrete" is also
made this way). For this reason it is not a good idea to completely separate the science of concrete
from the more mundane process of making it. No one expects contractors and construction workers
to manufacture plate glass, extrude pipe, or press drywall, but they are regularly expected to make
good quality concrete.
Designing the concrete mix: The first and most important step in the process is to determine
the ingredients that will make up the concrete and their proportions. As should be apparent from the
previous section, there are many variables to consider including cement type, aggregate size and
type, amount of water, and mineral and chemical admixtures. While a good mix design can still result
in inadequate or poor quality concrete if it is not executed correctly, a bad mix design will of course
always give poor results. Who is responsible for designing the mix depends on the type of project.
For large, publicly funded projects the responsibility for the final design falls to a licensed civil
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engineer. For residential projects such as foundations and driveways it is the private contractor,
whose professional reputation is generally his only credential. For do-it-yourself projects it is of
course the homeowner who must design his own mix.
Loads that must be supported:Concrete can be made with a wide variety of strengths, so this is
often the starting place for the mix design. Since the cost of concrete scales rather closely with its
strength, one does not want to make the concrete stronger than it needs to be. However, if the
application will only be supporting relatively small loads, it is usually not a good idea to specify weak
concrete, because weak concrete almost always lacks durability. For low load applications the quality
of the concrete is determined by other factors such as resistance to freezing or wear resistance.
Workability: The workability that is required depends primarily on how the concrete is to be
placed. Concrete can be poured, pumped, and even sprayed into place, and this will affect the
workability that is needed. Other factors such as the shape of the moulds, the rebar spacing, and the
equipment available at the site for consolidating the fresh concrete after it is placed must also be
considered. Workability is usually defined by the slump, which is the tendency for the fresh concrete
tends to spread out under its own weight when placed onto a flat surface.
Environmental conditions: If the concrete will be exposed to severe conditions, then this may
well determine the necessary concrete quality rather than the applied loads. In cold-weather
locations the concrete must be able to resist freezing. Roads and must be able to withstand the
corrosive effects of salt. Underground applications must be able to resist the ingress of moisture and
aggressive species fromthe soil. For almost any type of conditions or mode of attack, the most
effective defence is to keep the w/c low.
Surface wear: For some applications the physical loads tend to wear away the concrete instead of
breaking it. For roads, parking garages, driveways, and industrial floors the hardness and wear
resistance of the top layer of concrete will determine how long the structure lasts.
The ready-mix (batching) plant: Most concrete is batched and mixed in a central location called
a ready-mix plant and then trucked to the desired location. This is often the best solution even for
fairly small jobs. Ready-mix plants have a wide variety of aggregate and cement that are stored under
controlled conditions, as well as good equipment for weighing and mixing. As a result, the quality of
the concrete should be high and consistent. Concrete mixing trucks can be used to transport already
mixed concrete, or the mixing can actually be performed by the truck as it is travelling to the site.
One potential disadvantage of ready-mixed concrete is that the time required to transport the
concrete to the site may use up too much of the early period of good workability. This can generally
be handled through the use of retarding admixtures.
Mixing: Mixing of concrete is a very important step for achieving good final properties, and one
that can be quite difficult without the right equipment. This is one of the best reasons for using
ready-mixed concrete. Mixing distributes the aggregate evenly throughout the cement paste,
ensures that all of the cement has been fully saturated in water, and removes large air voids. In
addition, mixing breaks up agglomerated clusters of cement particles and allows air entraining
24. Page | 24
admixtures to generate the correct air void system. Under mixing leaves large flaws and thus results
in inferior strength, while over mixing wastes time and energy and can destroy entrained air voids.
The lower the workability, the more mixing energy and mixing time is required.
Placing:Once the concrete has been adequately mixed, it must be placed into the formwork that
defines its final position and shape. If the concrete is to be reinforced, the rebar must already be in
place so the concrete can flow around it. If the concrete mixing truck can be located close to (and
higher than) the site, then the concrete can be poured directly into the forms. In cases where this is
not possible, the concrete can be transferred in buckets by a crane or by wheelbarrow. When this is
impractical due to the distance required or the size of the job, the fresh concrete can be pumped
through a system of pipes or hoses to the site by special concrete pumps. Concrete that is to be
pumped has more stringent requirements for workability. If the concrete is too dry, it will not pump
well, while if it is too wet it will tend to segregate. Segregation can also occur if the concrete falls into
the formwork too quickly, as larger aggregate particles will tend to be driven downward.
Consolidation:Once the concrete is in place, it should be consolidated to remove large air voids
developed during placement and to make sure that the concrete has flowed into all of the corners
and nooks of the formwork. This process is also called compacting. Over consolidation can lead to
segregation and bleeding, but under consolidation is more common, resulting in less-than optimal
properties. The two most common methods of consolidation are vibration and roller compacting.
Vibration is a mechanical process that transfers pulses of shear energy to the concrete, usually by a
probe that is inserted several inches into the concrete. Each pulse of shear energy momentarily
liquefies the concrete, allowing it to flow very freely.
Curing: Once concrete has been placed and consolidated it must be allowed to cure properly to
develop good final properties. As the concrete hardens and gains strength it becomes less and less
vulnerable, so the critical time period is the first hours and days after it is placed. Proper curing of
concrete generally comes down to two factors, keeping it moist and keeping it supported. Hydration
of cement, as the word itself implies, involves reaction with water. To cure properly, the cement
paste must be fully saturated with water. If the relative humidity level inside the concrete drops to
near 90% the hydration reactions will slow, and by 80% they will stop altogether. Not only will this
prevent the concrete from gaining its full strength, but it will also generate internal stresses that can
cause cracking. To keep fresh and young concrete moist, it can be covered with plastic or damp fabric
to prevent evaporation, or sprayed periodically with water. Spraying is particularly helpful when the
w/c of the concrete is low, because the original mix water is not enough for the cement to hydrate
fully. The additional water will not penetrate through a thick concrete structure, but it will help
create a stronger surface layer. Pools of water should not be allowed to form on the surface,
however, as this will leach and degrade the concrete underneath.
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(Needle Type Vibrator)
E CONSTRUCTION OF METHODLOGY
Segment:
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About the segment:
Speed of erection
Crew efficiency
High quality
Many options
Top down erection possible minimal disruption to traffic and surface operations
Efficient use of forms
Transportation of long girders having spans more than 20m by trailor will pose serious problem in
crowded city roads and sharp curves.
Operation of Two cranes to place girders in position will require traffic block during night for a
number of night which may not be acceptable to traffic police and if agreed upon they will cause
inconvenience to general public. The availability of casting yard at suitable location as choice will be
governed by shifting, lifting and transportation of girders. Cast in situ construction, Where ever
required, is time consuming and cause inconvenience to public.
Type of Segment:
S1, S2, S3, S4, S5 & S6
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Diameter of Bar used:-
32mm
25mm
20mm
16mm
12mm
10mm
08mm
METHOD OF STATEMENT
A method statement is detailing the procedure of casting various elements of the structure. It is to be
prepared by the contractor and get it approved by the client or their nominated consultants well
before starting the construction work at site. It is a written document, available at site, to be referred
by the client and contractor, as and when required by them to ensure availability of required
infrastructure and proper sequence of the construction activities, so as to get the work done with
desire progress and quality.
Placing of inner mould and 15 hrs Day 3
Inspection by client 2 hrs Day 3
Pouring of concrete 10 hrs Day 4
Curing 72 hrs Day 4 – 6
Removal of inner shutters * 4 hrs Dar 4
Transfer of pre- stress 2 hrs Day 7
Cutting of strands 2 hrs Day 7
Lifting of girder 10 hrs Day 7
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About the pilling boring machine:
More than 600 piles, both 800 mm diameter and 1000 mm diameter, were installed for supporting
the proposed G+10commercial building with large column loads. The piles were in groups of 4 piles
to 10 piles. Hydraulically operated rotary piling procedure was adopted in the execution of these
piles. The boreholes were advanced using augers fitted to the rotary stem and the soil cuts were
frequently removed from the borehole by withdrawing the auger and then reintroducing it for
further advancement. Bentonite mud and bentonite powder was periodically introduced for
stabilizing the borehole sides and bottom. Temporary casing was provided to a depth of roughly 7.0
m from the working level. The ground water table was at about 1.50 m below the ground level during
the construction of piles. The soil cuts obtained from the auger blades were collected and identified
for establishing the pile termination depths. Relatively large size stones (pieces of weathered rock)
were collected by segregating large chunk of soil retrieved from the borehole. The depth of pile thus
executed was 10.50 m with respect to the typical profile.
The piling work completed and the site was handed over for superstructure construction. The
excavation was to be made to a depth of roughly 2.50 m for accommodating the thick pile caps
connecting 4 to 10 piles in a group. Many piles did not record concrete even after 2.50 m excavation.
Dipper excavations revealed pile concrete of almost required size.
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Gantry Girder:-
Gantry girders are basically used for carrying the moving load; means, to carry a heavy load in
industrial building we need to set up gantry girder along with the crane system; so, how to design
and what are the aspects of design procedures, those things we will discuss. Here the difference you
will get is that - one is the due to moving load; because of moving load what will be the maximum
bending movement and shear force of the, on the gantry girder for a particular position.
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Personal Safety
1. Wear protective equipments. Always wear safety helmet, safety vast and safety Foot wear at
construction site.
2. Do not drink or take drugs while working.
3. Pay attention to personal hygiene.
4. Do not play in the workplace.
Public Safety
1. Pay attention to public safety. Members of the public are often unaware of or do not understand
the work carried out on construction sites and the hazards involved.
2. Take great care to prevent the fall of materials from height.
3. Do not stack materials on floor edges or on scaffolds.
Safety Campaign
An organized movement launched by an enterprise or construction firm to advocate the safety rules
and regulations among its workers to reduce the number of accidents is termed as safety campaign.
The following points should be kept in mind for launching safety campaign:
1. The safety campaign must be placed under the charge of a very competent, experienced and able
manager, who may be termed as safety Director.
2. The worker should be frequently addressed in a small group in their language or easy accessible
language to explain about safety rules.
3. Do‘s and Don‘ts during construction work should be displayed in bold letter along with diagram on
chart paper
4. Advertisement films, Documentaries and CD should be shown to the workers on off days,
explaining about the need for safety measures.
5. Safety Slogans and safety Quotations should be made an integral part of safety campaign to
educate the illiterate and poor workers.
6. Training in first-aid should be provided to workers and supervisors for treating minor cuts and
injuries.
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7. Safety journals should be brought about by the concerned management and distributed free of
cost to the workers.
Some Important Notes
Grade of concrete used : M50
Grade of steel used : Fe500D
Clear Cover to Reinforcement
Exposed Faces : 40mm
Internal Faces : 35mm
Top Surfaces : 35mm
Minimum lap length : 44 X Dia. Of Bar
Minimum c/c distance b/w two adjacent lap : 1.3 times lap length
Curing : 14 days(Min.)
Aggregate used : 10mm & 20mm
Cement used : OPC 53
Length of one segment : 42m
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CONCLUSION
The entire period of Industrial Training has given me good & important practical exposure of
construction work. At the end of the Industrial Training under Larsen & Toubro Construction Ltd, I
feel myself better equipped and ready to face the field problems related to Civil Engineering works.
In these thirty days, I have learnt how to deal with Authorities and workers under supervision and I
have become familiar with the fact that the field work is much difficult from theoretical knowledge.
But until you don‘t have the theoretical knowledge, the practical work is very difficult to carry-out
and understand.
Working with experienced engineers has enhanced my technical skills to a great extent for which I
am grateful to them. Their professional approach towards work is appreciable. The training has
provided me with much needed field exposure to shape up my thinking in a better way as a
professional making me a lot more capable to face the challenges of life.
After the training we came to the following conclusions:
Summer training gives opportunity to differentiate between theoretical and practical aspects.
Understood the importance of coordination between planning, execution, safety, store
keeping, mechanical, electrical departments.
Learnt how to get work executed by the coordination of different peoples on site.
Learned many new things by visiting the sites and by the experience of the staff of L&T.
References:-
L&T Staff
Textbook of Surveying by B.C. Punamia
Textbook of BMC by Katsons
Textbook of Concrete technology
Lab Testing Handbook
IS: 456-2000 CODE for Concrete Design
IS: 800-1984/2007 CODE for Steel Design