DMRC Summer internship report for civil engineering students. Project- DMRC phase 3 (CC-34 & CC-32) Design and construction of tunnel and underground metro station

1. Summer Internship Report
18, May 2016 to 21, June 2016
Submitted by:-
Deepak Kumar
Roll No: 1301011044
4th
year undergraduate student,
Department of Civil Engineering,
DIT University, Dehradun

2. 1
1. ACKNOWLEDEMENT
I am very thankful to Delhi Metro Rail Corporation Ltd. for having given me the opportunity
to undertake my summer internship/training at their prestigious project Design and
construction of tunnel & underground metro station from Janakpuri West to Botanical Garden
(CC-32 and CC-34).
It was a very good learning experience for me to have worked at this site. I would like to
convey my heartiest thanks to Mr. Pramod Ahuja (CPM-5) who heartily welcomed me for the
training. I would also like to thanks Mr. Balwant Kumar (PM-5A), Mr. Manoj Bajpyee (PM-
5B), Mr. Rupesh Srivastava (SE Civil) and Mr. Pankaj Kumar (JE) who guided and
encouraged me all through the summer training.
Last but not the least; I would like to thanks all the staff at DMRC for being so helpful during
this summer training.

3. 2
2. PREFACE
Project gives an opportunity to implement the principles and knowledge practically. The
experience that one gets is wonderful because one study in books is different from what one
face in the field.
A project helps a student in getting acquainted with the manner in which his knowledge is
being practically used and this is normally different from what one has learnt from books.
Hence, when one switches from the process of learning to that of implementation his
knowledge, he finds an abrupt change. This is exactly why industrial training during the
B.Tech. Curriculum becomes all the more important.
Imagine large drives used in site, they are really effective and helpful. Also imagine of we
could control different machines and equipment at sites or industry by using another device.
My training includes these basic some important engineering needs in an industry.

4. 3
3. INTRODUCTION ABOUT THE ORGANIZATION
The Delhi Metro Rail Corporation Ltd. Abbreviated to DMRC, is a centre-state public sector
company that operates the Delhi metro. The DMRC was founded on 3 May 1995 at New
Delhi, India by E. Sreedharan, serving as the first managing director E. Sreedharan handed
over charge as MD of DMRC to Magnu Singh on 31 December 2011.
The DMRC is also involved in the planning and implementation of metro rail, mono rail and
high speed rail project in India and abroad. DMRC has served as the project consultant and
has prepared detailed project report (DPR) for every metro and mono rail project in India,
except the Kolkata Metro and Chennai MRTS.
The DMRC has been certified by the United Nations as the first metro rail and rail-based
system in the world to get “carbon credits for reducing greenhouse gas emissions” and
helping in reducing pollution level in the city.

5. 4
4. PROJECT DETAILS
4.1. Site Location
Fig: Site location
I am very thankful to DMRC for given me the opportunity to learn the practical aspect of
civil engineering work on their prestige project. During first week of my training I was
exposed to CC32 (UG-3) which is located next to Indira Gandhi domestic airport. And after
that I was allowed to go CC34 (UG-5) which is located near existing Janakpuri West metro
station in order to complete my industrial training.

6. 5
4.2. Site map of CC32
Fig: Master plan of CC32(UG-3)
Fig: detail plan of cross over-1 cc32
4.3. Site Map of CC34
Fig: Plan of cross-over 2 CC34

7. 6
Fig: Plan of undercroft level
4.4. About the Project
Key details about CC34(UG-5)
Client DMRC
Location Delhi
Contract Type Design and construction basis.
Contractor HCC-Samsung JV (Share 50 : 50) and HCC is leader
Completion period 46 months (18 Feb. 2013 ~ 01 Dec. 2016)
Contract Value 865.98 Cr. (A = 812.04, B = 41.18, C = 12.76)
Scope of work Design and construction of
 Twin tunnel between ch. 830.912 and 4591.63 by shield
TBM. (4.363 KM Each)
 0.113 km and 0.158KM long Crossovers on either side of
Janakpuri station by C/C Method.
 U/G Stations at Janakpuri West, Dabri Mor and
Dashrathpuri including architectural finishing of stations.
 Interchange facilities between old and new Metro station
at Janakpuri.

8. 7
PPE
5. SAFETY INDUCTION
In safety induction safety engineer told us about the use of safety equipment and PPE
(Personal Protective Equipment) at construction site.
5.1. PPE(Personal Protective Equipment)
Fig: safety Glasses
Fig: Safety Gloves
Fig: Safety shoes
Fig: Nose Mask
Fig: Ear Plug
Fig: safety helmet

9. 8
5.2.Colour Code for Safety Helmets
Safety Helmet colour Person to Use
White All DMRC staff
Grey All Designer, Architect, Consultants etc
Violet Main Contractors(Engineers/Supervisors)
Blue All Sub -Contractors (Engineers/Supervisor)
Red Electricians ( Both Contractor & Sub contractor
Green Safety Professionals ( Both Contractor& Sub contractor
Orange Security Guards/ Traffic Marshals
Yellow All Workmen
White(with visitor sticker) Visitors

10. 9
6. SURVEYING DURING WORK
Site surveys are detailed studies carried out to supplement and verify site information
provided by the client. During execution the surveying is important to identify the location,
defining the level. Moreover during execution, project of any magnitude is constructed along
the lines and point established by surveying.
1. Auto Level
2. Total Station
6.1 Auto Level
Modified version of dumpy level is known as auto level
which is a levelling instrument, or auto level is an optical
instrument used to establish or verify points in the same
horizontal plane. It is used in surveying and building with
a vertical staff to measure height differences and to
transfer, measure and set heights.
Apparatus used Fig: Auto Level
Tripod stand, auto level, shaft, meassuring tap
Procedure
1. Set the tripod in level(3 legs sre level and equal).
2. Set auro level on tripod stand.
3. Set bubble in centre.
4. Read the reading in cross hair level.
Observation Table for Calculation
Station B.S. I.S. F.S. H.L. R.L.
Where
B.S- Back Sight
I.S.- Intermediate Sight
F.S.- Fore Sight
H.I.- Height of Instrument
R.L.- Reduced Level
Fig: showing number of station

11. 10
Formulae:-
H.I = R.L + B.S
F.S = H.I – R.L of staff in fore direction
6.2 Total Station
A Total Station is a modern surveying instrument that
integrates an electronic theodolite with an electronic distance
meter. The total station is an electronic theodolite (transit)
integrated with an electronic distance meter (EDM) to read
slope distance from the instrument to a particular point.
Function of total station:-
1. Angle Measurement
2. Distance Measurement
3. Coordinate Measurement
4. Data Processing

12. 11

13. 12
7. TUNNEL OVERVIEW
FIG: Constructed Tunnel
KEY POINTS ABOUT TUNNEL:-
 Tunnels are constructed with the help of TBM (tunnel
Boring Machine)
 The type of tunnel is “twin tunnel”.
 Inner diameter of tunnel is 5.8m
 Outer diameter is 6.5m
 There are 6 segment key in one ring of thickness
275mm and length 1.4m
 A cross passage is provided after every 200 rings for
emergency exit.
 The lowermost of the tunnel is 20m below the ground
surface.
Fig: tunnel location below GS

14. 13
8. TBM (Tunnel Boring Machine)
A tunnel Boring machine also known as “mole“, is a machine used to excavate tunnels with a
circular cross section through a variety of soil and rock strata. They can bore through
anything from hard rock to sand. Tunnel diameter can range from a meter (done with micro-
TBM) to 19.25 meter to date.
Fig: TBM (Tunnel Boring Machine)
Tunnel boring machine are used as an alternative to drilling and blasting methods in rock and
conventional “hand mining “in soil. TBM have the advantages of limiting the disturbance to
the surrounding ground and produced a smooth tunnel wall. The major disadvantage is the
upfront cost. TBMs are expensive to construct, and can be difficult to transport. However, as
modern tunnels become longer, the cost of tunnel boring machines versus drill and blast is
actually less.

15. 14
9. WATER PROOFING
Roof slab waterproofing using Master Seal Roof 3500
This waterproofing system is multi-layered and comprise of a series of substrate sealers,
primers and waterproofing membrane.
Fig: Masterplan for waterproof
s.no Description Product Consumption Packing
1 Primer Master Seal P2525 0.40 Kg/m2 Master Seal
P2525 Pack: 3Kg
2 Sand
Broadcasting
Oven Dried Silica Sand
(.3-.8mm) Master top
SRA No3
0.8-1.0 kg/ m2 Pack: 25 kg
3 Waterproofing
Membrane
Masterseal M800-Part A,
Grey
MasterSeal M800- Part B,
un-pigmented
2.65Kg/m2 Part A: 210 Kg
Part B: 220 Kg
The seamless, Monolithic waterproofing will obtain from the CONIROOF system in several
application stages:

16. 15
9.1. Surface preparation
Uneven concrete should be leveled to produce a smooth, flat surface. For heavy wear
situation a repair mortar Master Emaco S 488 will be used and bug holes will be repaired by
using epoxy putty Master Brace 2200.
Finally ensure the surface is dust free by using an industrial vacuum cleaner.
Fig: cleaning of surface
10.
11.
12.
Fig: surface grindig Fig: surface dressing
9.2. Pre-Application condition
The moisture level on the substrate will be ensured below 4% at the time of application of
MasterSeal Roof system and the application will be avoided if the humidity is high or if it
rains. Application of the primer should be avoided if the temperature will fall below 10 C and
if incase of high temperature above 30 C, application will be done in falling temperature.

17. 16
Fig: Drying of the surface Fig: moisture checking
9.3. Preparation for Primer coat
Epoxy primer Master Seal P 2525 should be applied with hand brush at the consumption rate
mention in the table to ensure that the primer has
Fig: primer coat
got absorbed properly by pores or micro pores of the concrete surface and it applied
homogeneously by the complete surface.
Graded aggregate will be sprinkled immediately after applying primer to the surface properly.
9.4. Spraying of MasterSeal M 800 membrane
A solvent free, two components, SPRAY applied waterproofing membrane will be sprayed
by special, two components spray equipment. Required thickness of membrane minimum 2.5
mm will be checked with the help of thickness gauge.

18. 17
Fig: spraying of Master Seal M800 membrane
9.5Test
Thickness of the membrane is checked
And the roof is checked for any leakage by ponding test
Fig: ponding test
9.5. Treatment of construction joint
1. Cutting grooves of 25X25mm at construction joint of roof slab/wall with the help of
suitable mechanical equipment.
2. All the loose particles, dust etc will be cleaned with the help of wire brush and air
blower.
3. Removal of any type of contamination will be ensured.
4. Groove will be pre-saturated with water before application.

19. 18
5. MasterSeal 502 will be mixed with water as recommended in product technical data
sheet.
6. Mixed material will be poured in the groove with proper compaction.
7. MasterSeal M800 membrane will be sprayed as per the method statement.
Fig: construction joint

20. 19
10.METHOD FOR REINFORCEMENT WORK
1. All reinforcement shall be placed above the ground by using PVC cover
block or concrete blocks.
2. For reinforcement, care shall be taken to
protect the reinforcement 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. Fig: PVC cover block
4. Reinforcement shall be tied as per the latest GFC drawing and any
Fig: reinforcement of slab
extra bars provided at site shall be recorded in the pour card/ lap register.
5. Unusable cut rods and scrap reinforcement shall be properly placed at
yard.

21. 20
11. BAR BENDING SCHEDULE:
1. Prepare bar bending schedule based on the latest GFC drawings and to be
submitted to Engineer for review
2. Bar bending schedule shall clearly specify the following:
a. Bar diameter,
b. Numbers,
c. Cut-lengths,
d. Shapes.
3. Bar bending schedule 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.
s.no Member
name
Bar
mark
no.
Sketch Dia
of
bar
Cut
Length
Bending
dimension
No.
of
sets
No.
of
bar
per
set
Total
no.
of
bar
Total
cut
length
Unit
weight
Total
weight
mm m mm m Kg/m KG

22. 21
12.OVERLAPPING OF BARS
Staggering of reinforcement shall be carried out in such a manner that not
more than 50% lapping be provided at any section.
Fig: overlapping of bars
13. REBARING
Rebaring is the method of insertion of steel bars when:-
1. There is change in design or there is some extension of present structure.
2. When steel rod as per has been not installed and to install the same
rebaring

23. 22
Fig: cleaning of holes Fig: rebaring
work
Mostly HILTI chemical are used for rebaring
Steps involved:-
1. Drilling in the existing structure as per drawing
2. Cleaning of holes by ELE blower
3. Filling of chemical in well cleaned holes
4. Then inserting bars slowly inside the holes

24. 23
14. CUTTING, BENDING & PLACING:
1. All reinforcement shall be free from loose mill scales, loose rust and coats of paints,
oil, mud or any other substances which may destroy or reduce bond. Use wire brush
to clean the reinforcement.
2. Cutting and bending shall conform to the details given in the approved bar bending
schedule.
a. Cutting of Rebar by heat is not permitted, only by grinding or shearing is
permitted.
b. No heating is allowed to facilitate bending of rebar
Fig: cutting of steel bars
3. Place the reinforcement as per GFC drawings ensuring the following aspects properly.
a. Type & size of bar,
b. Number of bars,
c. Location and lengths of laps, splices.
d. Curtailment of bars.
e. In two way reinforcement, check the direction of reinforcement 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 18g soft GI annealed binding wire.
4. Reinforcement may be placed with in the following tolerance whenever required:
a) For effective depth 200mm or less ±10mm.
b) For effective depth more than 200mm ±15mm.
c) The cover shall in no case be reduced by more than one third of the specified cover
or 0 /+ 10mm.
d) The cover should suit various cover requirements as per Drawing Notes.
5. The sequence of reinforcement shall be correlated with fixing of inserts, sleeves,
conduits, anchors and formworks.

25. 24
6. In walls, place accurately bent spacer bars wired to vertical or horizontal bars between
successive rows.
7. No steel parts of spacers sure allowed inside the concrete cover. Spacer
8.
b
Fig: placing of steel reinforcement of the slab
locks 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.
9. Spacers, cover blocks should be of concrete of same strength or PVC
10. 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 reinforcement.
11. Spacers or chairs should be placed at a maximum spacing of 1.0 mtr and closer
spacing may sometimes be necessary.
12. All reinforcement shall be placed and maintained in the positions shown in the
drawing by providing proper cover blocks, spacers, Supporting bars.
13. Rough handling, shock loading (Prior to embedment) and the dropping of
Reinforcement from a height should be avoided. Reinforcement should be secured
against displacement.

26. 25
15. METHOD FOR CONCRETING
15.1. Placing of concrete
1. Concrete pump with pipeline is used for conveyance of concrete to the pouring area.
2. Concrete for the slab is placed in approx. 400mm-450mm thick layers each. Each
layer is compacted before the next layer is placed.
3. Concrete is carefully worked around all reinforcement and embedded fixtures and
corner of formwork.
4. The top surface of the concrete is leveled with aluminum box section of 3m long
followed by steel trowel to produce the required surface finish.
5. Concrete placing is uninterrupted until placing of a section as defined by construction
joints is completed.
6. The concrete at the surface of cold joints is cleaned with a high pressure air water jet
before the concrete achieves a primary set to provide an
Fig: placing of concrete over reinforcement for roof slab
irregular clean surface free from laitance. Prior to restarting concreting, the surface will
be wetted.
7. Maximum free fall of concrete will be limited to 1.5m.
8. The temperature of the concrete should not exceed the limiting temperature
mentioned in the plan.

27. 26
15.2. Compaction of concrete
Concrete is compacted during placing by immersion vibrators. An immersion vibrator is
operated in a near vertical position, and it penetrate the full length of the layer of concrete
placed and just into
the layer below to
stich in between.
Vibration will be
applied continuously
until the expulsion of
air has practically
ceased. The vibrators
will be withdrawn
slowly to avoid the
formation of voids.
Fig: positions of immersion vibrators
During the compaction care will be taken to avoid the displacement of reinforcement,
formwork, pre-fixed pipes, etc.
A minimum of one standby vibrator will be provided during concreting.
Fig: compaction of concrete
15.3. Curing of concrete
The following procedure will be followed in curing the slab concrete.
15.3.1 Horizontal Surface
a. As part of the slab is concreted up to final level including final surface finishing, the
finished surface will be covered with hessian cloth.

28. 27
b. The hessian will be kept permanently damp by periodical spray of water through
water hoses or by ponding arrangement in lieu of hessian cloth. The curing will be
continued for 14 days.
Fig: Horizontal Surface Curing
15.3.2 Vertical Surface
The curing of vertical surface of slab, walls or columns will be continued covered with
hessian cloth and kept damp by periodical spray of water for 10 days
Fig: Vertical Surface Curing

29. 28
16.METHOD FOR FORMWORK
16.1. Pre Check
1. Check if the shutters are properly cleaned by removing the concrete/ mortar and
protruding nails.
2. Formwork shall be made to the exact dimensions within the permissible tolerances as
mentioned below.
3. Required thickness and quality of plywood conforming to IS 6461 shall be used to
meet the requirements of design and surface finish.
4. For beam bottom & sides, proper size of timber at required spacing shall be provided
to take the design loads/ pressure considering sleeves, conduit anchors & inserts.
16.2. Erection of formwork
1. Sufficiently rigid and tight to prevent the loss of grout or mortar from the concrete.
2. Capable of providing concrete of the correct shape and surface finish within the
specified tolerance limits.
3. Soffits forms capable of imparting a camber if required.
4. .The formwork may be of timber, plywood, steel, plastic or concrete depending upon
the type of finish specified.
5. Erect staging/shuttering as per drawing/sketches in such a way that de-shuttering can
be done easily including provision for re-propping, if planned.
6. Check the location, line, level, plumb and dimensions of the formwork to ensure that
the deviations are within the permissible limits.
7. Provide bracing at proper places & intervals as specified by the manufacturer or as per
formwork scheme to take care of lateral loads.
8. Apply mould oil/other coatings as release agents before reinforcement steel is placed.
9. Wire ties passing through beams, columns and walls shall not be allowed .In their
place bolts passing through sleeves shall be used .For liquid retaining structures,
sleeves shall not be provided for through bolts.
10. Check all the shutters are properly aligned and fixed firmly with required lateral
supports and ties.
11. Check all the spanning members have proper bearing at the supports.
12.Wedges or jacks shall be secured in position after the final check of alignment.
13. Forms shall be thoroughly cleaned of all dirt, mortar and other matters such as metals,
blocks, saw dust and foreign materials before concreting if required through clean-out
openings.
14. Check all the gaps/openings are properly closed to avoid leakages.

30. 29
15. Check all the inserts/embedment and openings are exactly placed as per the drawings.
16. In case of leakages, bulging and sagging immediate actions shall be taken by
tightening wedges or adjusting by jacks which must be done before the concrete takes
its initial set
.
16.3. Removal of Forms
1. Formwork components shall not be dropped but shall be lowered without damage to
the components and structures. All the removed formwork materials shall be
thoroughly scarped, cleaned immediately and stacked properly for reuse.
2. 'All forms shall be removed after the minimum period stipulated mentioned below
without damage to the concrete including removal without shock as per IS 456

31. 30
17. METHOD FOR BACKFILLING
17.1 Procedure for bottom-up construction
1. The backfill material used shell be suitable earth complying with the required
specification,
2. Timber lagging if any between soldier piles shall be removed for 1.5 m at a time above
the excavated level and backfilling with soil of @300mm compacted thickness layer is
done initially.
3. Compaction of each layer is done using plate compactor and whereas space constraint is
there manual tamping will be done.
4. The soil is compacted till 95% compaction is achieved for each layer.
5. Dumping, spreading and compaction of soil is continued in layers of @300mm until the
level of working height for laying water proofing membrane below the roof slab top
level, is reached.
6. Waterproofing membrane is sprayed over the roof slab.
7. Once roof slab top level is reached on one side, soil is dumped above the roof slab to be
spread on the other side of tunnel box section.
Fig: backfilling
8. Steps 1 to 5 are repeated for the other side, and space between tunnels boxes, wherever
applicable.
9. Once roof slab top level is reached more soil is dumped over the roof slab. Soil is
backfilled and spread in layers of 200mm .
10. Compaction of soil layers is done above roof slab top level using Tandem vibratory
walk behind rollers, plate compactor.
11. Dumping, spreading and compaction of soil is done in layers of @200mm until the strut
level above is reached.
12. The procedure of dumping, spreading and compacting the soil in layer of 200mm are
repeated until the next strut level above/ ground level is reached.

32. 31
13. Compaction test shall be conducted in 1200cum of each layer
17.2. Procedure for Top-Down construction
1. The backfill material used shell be suitable earth complying with the required
specification
2. Waterproofing membrane is sprayed over the roof slab.
3. Dumping, spreading and compaction of soil are done in layer of @ 300 mm compacted
thicknesses until the desired compaction level is achieved.
4. Compaction of soil layers is done above roof slab top level using Tandem vibratory
walk behind rollers, plate compactor.
5. The soil is compacted till 95% compaction is achieved for each layer and testing
requirement shall be as per criteria specified.
Fig: compaction of backfill by roller
17.3. Procedure for areas having Utilities
1. The backfill material used shall be suitable earth / fine sand complying with the required
specification.
2. Compaction of soil layer is done using rammer, plate compactor and manual compaction
will be done. Special care is taken during the the compaction such that utilities are not
damaged during the compaction.
3. Dumping, spreading and compaction of soil are done in layer of @ 200 mm compacted
thicknesses until the desired compaction level is achieved.
4. The soil is compacted till 95% compaction is achieved for each layer and testing
requirement shall be as per criteria specified.

33. 32
18. BLOCK WORKS
18.1. Materials
The following materials are required :-
 Pre cast solid cement concrete blocks (LxWxH).
400x200x200mm/ 400x200150mm/ 400x200x140mm/ 400x200x100mm as
mentioned in approved
drawing.
 Mortar sand
 Cement(53grade OPC)
 Wire mesh
 Steel bars
18.2. Work Procedure
 Handling of pre cast solid cement concrete block
 Setting out the wall locations
 Production of mortar at site
 The proportion of cement and sand in the mortar shall be cement : sand = 1:4 (without
any additives)
 Kinker construction for cavity wall
 Laying of blocks
all the blocks shall be moist nearly half an hour and again immediately befor laying.
1. Stand and set lumbers with a straight edges along the vertical line of wall face to
vertical alignment of the work.
2. Then stretch a string line indicting the top level of the starting course
3. Top of concrete slab, from which block are laying up, should be kept clean and
wet.
4. Lay the blocks for the course with a uniform thickness of horizontal joint.
5. Standard length of block is 400mm and in case a cut unit is required to make up
the course, place that unit made of standard unit at least one block away from the
concrete column, quoins of the wall or service openings including doors and
windows.
6. After finishing the course,carry out jointing with the steel trowel to strike off
joints slightly lower than the block face in case plastering or rendering are not
required at a later stage. However, only where plastering is required, take out
joints to a depth of between 10mm to 15mm as the works proceeds, to give an
adequate key to plastering.
7. Repeat sequence for the next course.

34. 33
Fig: showing mesh wire and steel bar Fig: block work in front of retaining wall

35. 34
19. QUALITY ASSURANCE & QUALITY CONTROL
Quality is the key component which propels performance and defines leadership traits. At
Delhi Metro Rail Corporation Ltd., Quality Standards have been internalized and documented
in Quality Assurance manuals. DMRC recognizes the crucial significance of the human
element in ensuring quality. Structured training programmes ensure that every employee is
conscious of his/her role and responsibility in extending DMRC Construction’s tradition of
leadership through quality. Relevant procedures established clearly specify the criteria and
methods for effective operation, control and necessary resources and information to support
the operation and monitoring of these processes.
19.1 TESTS ON CEMENT
19.1.1 CONSISTENCY
AIM
To determine the quantity of water required to produce a cement paste of standard
consistency as per IS: 4031 (Part 4) - 1988.
PRINCIPLE
The standard consistency of a cement paste is defined as that consistency which will permit
the Vicat plunger to penetrate to a point 5 to 7mm from the bottom of the Vicat mould.
APPARATUS
VICAT APPARATUS
Vicat apparatus conforming to IS: 5513 - 1976 Balance, whose permissible variation at a load
of 1000g should be +1.0g Gauging trowel conforming to IS: 10086 - 1982
PROCEDURE
i) Weigh approximately 400g of cement and mix it with a weighed quantity of water.
The time of gauging should be between 3 to 5 minutes.
ii) Fill the Vicat mould with paste and level it with a trowel.
iii) Lower the plunger gently till it touches the cement surface.
iv) Release the plunger allowing it to sink into the paste.
v) Note the reading on the gauge.
vi) Repeat the above procedure taking fresh samples of cement and different quantities of
water until the reading on the gauge is 5 to 7mm.
REPORTING OF RESULTS
Express the amount of water as a percentage of the weight of dry cement to the first place of
decimal.
19.1.2. INITIAL AND FINAL SETTING TIME
AIM
To determine the initial and the final setting time of cement as per IS: 4031 (Part 5) -1988.
APPARATUS

36. 35
Vicat apparatus conforming to IS: 5513 - 1976 Balance, whose permissible variation at a load
of 1000g should be +1.0g Gauging trowel conforming to IS: 10086 - 1982
PROCEDURE
i) Prepare a cement paste by gauging the cement with 0.85 times the water required to give a
paste of standard consistency.
ii) Start a stop-watch, the moment water is added to the cement.
iii) Fill the Vicat mould completely with the cement paste gauged as above, the mould resting
on a non-porous plate and smooth off the surface of the paste making it level with the top of
the mould. The cement block thus prepared in the mould is the test block.
INITIAL SETTING TIME
Place the test block under the rod bearing the needle. Lower the needle gently in order to
make contact with the surface of the cement paste and release quickly, allowing it to
penetrate the test block. Repeat the procedure till the needle fails to pierce the test block to a
point 5.0 ± 0.5mm measured from the bottom of the mould . The time period elapsing
between the time, water is added to the cement and the time, the needle fails to pierce the test
block by 5.0 ± 0.5mm measured from the bottom of the mould, is the initial setting time.
FINAL SETTING TIME
Replace the above needle by the one with an annular attachment.
The cement should be considered as finally set when, upon applying the needle gently to the
surface of the test block, the needle makes an impression therein, while the attachment fails
to do so. The period elapsing between the time, water is added to the cement and the time, the
needle makes an impression on the surface of the test block, while the attachment fails to do
so, is the final setting time.
REPORTING OF RESULTS
The results of the initial and the final setting time should be reported to the nearest five
minutes.
19.2. TESTS ON AGGREGATES
19.2.1. SIEVE ANALYSIS
AIM
To determine the particle size distribution of fine and coarse aggregates by sieving as per IS:
2386 (Part I) - 1963.
PRINCIPLE
By passing the sample downward through a series of standard sieves, each of
decreasing size openings, the aggregates are separated into several groups, each of which
contains aggregates in a particular size range.
APPARATUS
A SET OF IS SIEVES
i) A set of IS Sieves of sizes - 80mm, 63mm, 50mm, 40mm, 31.5mm, 25mm, 20mm, 16mm,
12.5mm, 10mm, 6.3mm, 4.75mm, 3.35mm, 2.36mm, 1.18mm, 600μm, 300μm, 150μm and
75μm
ii)Balance or scale with an accuracy to measure 0.1 percent of the weight of the test sample

37. 36
PROCEDURE
i) The test sample is dried to a constant weight at a temperature of 110 + 5oC and weighed.
ii) The sample is sieved by using a set of IS Sieves.
iii) On completion of sieving, the material on each sieve is weighed.
iv) Cumulative weight passing through each sieve is calculated as a percentage of the total
sample weight.
v) Fineness modulus is obtained by adding cumulative percentage of aggregates
retained on each sieve and dividing the sum by 100.
REPORTING OF RESULTS
The results should be calculated and reported as:
i) the cumulative percentage by weight of the total sample
ii) the percentage by weight of the total sample passing through one sieve and
retained on the next smaller sieve, to the nearest 0.1 percent.
19.2.2. WATER ABSORPTION
AIM
To determine the water absorption of coarse aggregates as per IS: 2386 (Part III) -1963.
APPARATUS
i) Wire basket - perforated, electroplated or plastic coated with wire hangers for suspending it
from the balance
ii) Water-tight container for suspending the basket
iii)Dry soft absorbent cloth - 75cm x 45cm (2 nos.)
iv)Shallow tray of minimum 650 sq.cm area
v) Air-tight container of a capacity similar to the basket
vi) Oven SAMPLE A sample not less than 2000g should be used.
PROCEDURE
i) The sample should be thoroughly washed to remove finer particles and dust,
drained and then placed in the wire basket and immersed in distilled water at a
temperature between 22 and 32oC.
ii) After immersion, the entrapped air should be removed by lifting the basket and allowing it
to drop 25 times in 25 seconds. The basket and sample should remain immersed for a period
of 24 + 1⁄2 hrs. afterwards.
iii) The basket and aggregates should then be removed from the water, allowed to drain for a
few minutes, after which the aggregates should be gently emptied from the basket on to one
of the dry clothes and gently surface-dried with the cloth, transferring it to a second dry cloth
when the first would remove no further moisture.The aggregates should be spread on the
second cloth and exposed to the atmosphere away from direct sunlight till it appears to be
completely surface-dry. The aggregates should be weighed (Weight 'A').
iv) The aggregates should then be placed in an oven at a temperature of 100 to 110oC for
24hrs. It should then be removed from the oven, cooled and weighed (Weight 'B').
REPORTING OF RESULTS
Water absorption = [(A-B)/B] x 100%

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19.3. TESTS ON CONCRETE
19.3.1 SLUMP
AIM
To determine the workability of fresh concrete by slump test as per IS: 1199 - 1959.
APPARATUS
i) Slump cone
ii) Tamping rod
PROCEDURE
i) The internal surface of the mould is thoroughly cleaned and applied with a light coat of oil.
ii) The mould is placed on a smooth, horizontal, rigid and non- absorbent surface.
iii) The mould is then filled in four layers with freshly mixed concrete, each
approximately to one-fourth of the height of the mould.
iv) Each layer is tamped 25 times by the rounded end of the tamping rod (strokes are
distributed evenly over the cross- section).
v) After the top layer is rodded, the concrete is struck off the level with a trowel.
vi) The mould is removed from the concrete immediately by raising it slowly in the vertical
direction.
vii)The difference in level between the height of the mould and that of the highest point of
the subsided concrete is measured.
viii) This difference in height in mm is the slump of the concrete.
REPORTING OF RESULTS
The slump measured should be recorded in mm of subsidence of the specimen during the test.
Any slump specimen, which collapses or shears off laterally gives incorrect result and if this
occurs, the test should be repeated with another sample. If, in the repeat test also, the
specimen shears, the slump should be measured and the fact that the specimen sheared,
should be recorded.
19.3.2. Compressive strength test/cube test
Out of many test applied to the concrete, this is the utmost important which gives an idea
about all the characteristics of concrete.
Preparation of cube specimens
MOULD
The mould shall be of size 15cm X 15cm X 15cm for the
maximum nominal size of aggregate not exceeding 40mm. Each
mould shall be provided with base plate having a plane surface and
made of non-absorbent material. Fig: Mould
SAMPLE OF CONCRETE

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Sample of concrete for the test specimen shall be taken at the mixer or in the case of ready
mixed concrete from the transportation vehicle discharge or as directed by Engineer-in-
charge.
SAMPLING
1. Clean the mould and apply oil.
2. Fill the concrete in the mould in layer approximately
5cm thick.
3. Compact each layer with not less than 35 strokes per
layer using a tampering rod (steel bar 16mm diameter
and 60cm long, bullet pointed at lower end) fig: concrete cube sample
4. Level the top surface and smoothen it with trowel
CURING
The test specimens are then stored in moist air for 24
hours and after this the specimens are marked and
removed from the molds and kept submerge in clear
fresh water until taken out prior to test.
Fig: curing of concrete cubes
TESTING PROCEDURE
1. Remove the specimens from the water after specified time and
wipe out excess water from the surface
2. Take the dimension of the specimen to the nearest 0.2m
3. Clean the bearing surface of the testing machine
Fig: cube testing
4. Place the specimen in the machine in such a manner that the
load shall be applied to the opposite side of the cube cast.
5. Rotate the movable portion gently by hand so that it touches the
top surface of the specimen
6. Apply the load gradually without shock and continue till the
specimen fail Fig: compressive testing
7. Record the maximum load and note any unusual features in the type of failure.

40. 39
Compressive strength of different grades of concrete at 7 and 28 days
Grade of
Concrete
Minimum compressive
strength N/mm2 at 7 days
Specified characteristic compressive
strength (N/mm2) at 28 days
M15 10 15
M20 13.5 20
M25 17 25
M30 20 30
M35 23.5 35
M40 27 40
M45 30 45
19.4. IN-SITU DRY DENSITY
19.4.1CORE CUTTER METHOD
AIM
To determine the in-situ dry density of soil by core cutter method as per IS: 2720 (Part
XXIX) - 1975.
APPARATUS
i) Cylindrical core cutter
ii) Steel dolley
iii) Steel rammer
iv) Balance, with an accuracy of 1g
v) Straightedge
vi) Square metal tray - 300mm x 300mm x 40mm
vii) Trowel
PROCEDURE
i) The internal volume (V) of the core cutter in cc should be calculated from its
dimensions which should be measured to the nearest 0.25mm.
ii) The core cutter should be weighed to the nearest gram (W1).
iii) A small area, approximately 30cm square of the soil layer to be tested should be exposed
and levelled. The steel dolly should be placed on top of the cutter and the latter should be
rammed down vertically into the soil layer until only about 15mm of the dolly protrudes
above the surface, care being taken not to rock the cutter. The cutter should then be dug out
of the surrounding soil, care being taken to allow some soil to project from the lower end of
the cutter. The ends of the soil core should then be trimmed flat in level with the ends of the
cutter by means of the straightedge.
iv) The cutter containing the soil core should be weighed to the nearest gram (W2).
v) The soil core should be removed from the cutter and a representative sample should be
placed in an air-tight container and its water content (w) determined.
REPORTING OF RESULTS
Bulk density of the soil γ = (W2 −W1)/V g /cc
Dry density of the soil γd = [100γ/100+w] g c

41. 40
20. CONCLUSION
From the field study report, it is evident that the construction activity is going on full swing
using all the safety norms as per ISO. It was a wonderful learning experience at Delhi Metro
Rail Corporation Ltd. for 5 weeks at CC32(UG-3) and CC34(UG-5). I gained a lot of insight
regarding several aspect of site. I was given exposure in almost all the departments at the site.
The friendly welcome from all the employees is appreciating, sharing their experience and
giving their peace of wisdom which they have gained in long journey of work. I am very
much thankful for the wonderful accommodation facility from DMRC. I hope this experience
will surely help me in my future and also in shaping my career.