PRESENTED BYAJAY SHAHU(20100872)

Industrial Training Report onResidential building(G+3)

(2012-13)

Content

1. Introduction2. Centre line plan 3. Foundation of Structure4. Preparation prior casting of slab5. Equipment 6. Volume of concrete7. Activities carried out after casting of slab8. Conclusion 9. References

1.Introduction

• It is a residential building having a proposal of 7-2bhk flat.

• Site location:- Goddhni, Nagpur• Plot area:-3600sft• Plinth area:-1100sft• Slab area:-1559sft• Number of flats:-7 flats• Builder name:- Kishore Dhawas• Name of firm:-City developers, Nagpur• Architect: - Samir Deshmukh• Structural designer: - Prasanna Kulkarni • Site engineer: - Ajay D. Shahu• Work duration:-7june to 7july

2.Centreline Plan

CENTRE LINE PLAN.

3.Foundation of the Structure A. Single Spread Slope Footing

• The base of the column is enlarged or spread to provide individual support for the load.

• A spread slope footing is a type or shallow foundation used to transmit the load of an isolated column to the subsoil.

• Numbers of footing provided=19 no.• Size of footing F1= (1500×1600), F2= (1500×1400)

B. Sectional detail

F1= (1500×1600), F2= (1500×1400)

F1= (1500×1600),

•It is a cress section of footing, showing the reinforcement at the bottom of footingand in the column.

C. Foundation Plan

4. PREPARATION PRIOR TO CASTING OF SLAB:- A. Level fixing

To maintain the slab at same an accurate level, i.e. all the four corners of inner face the slab are must be at same height from the floor level. Thus, to maintain the slab at same height, levelling is carried out by using

level pipe, thread and Tape.

B. Formwork: - The formwork is built on site out of timber, plywood and particleboard.

Use and application of centring can be made in following manner:-

Fixing Column caps Fixing beam bottom(wooden plank having

width of beam)Providing support-Lumbers or props to

rafters or spanLaying steel plates or plywood for slab

Column caps, beam bottoms With beam sides and proving Support.

Laying steel plates over Rafter or span

C. Checking of mould formed by formwork

After completing all shuttering work, the next step is to check that the available dimension over formwork (dimension of mould) is same as required for beam, column, duct and slab.

Checking the length, width and depth of beam, slab area over each room is same as specified dimension.

If any dimension of mould is found incorrect, then it is corrected at the same time.

D. Line and Levelling:-

Levelling is done in order to obtain flat and horizontal slab.

E. Oiling surface of formwork

A thin single layer of burned engine oil is applied manually over the surface of formwork. Advantage:-

a.To prevent the corrosion.b.To prevent the absorption of slurry.c.To fill the fine gaps, voids and various joints.d.To prevent the spilling of concrete slurry.e.To loosen the bond between roofing material of

formwork and the roof of slab, thus removing the formwork easily.

f. To increase the life of both steel, wood and ply formwork . 

F. Reinforcement cutting and binding

The diameter, length and number of the bar required can be obtained from the structural drawing and bar bending schedule of the slab.

Cutting Bending Centre-to- centre distance is marked over formwork surface This marking referred as the point to lay longitudinal and

transverse bars. In case of beams, the centre-to-centre distance between two ties

is marked on the longitudinal bars of that beam. Then the ties are placed and tied with binding wire at that point. After bar-binding work is over, engineer checks the

reinforcement of the slab before casting and thus get corrected.

BAR BENDER BINDING TIES

G. Providing Cover: -

Cover is the distance between the centre of the road and the periphery of the structural member. Minimum cover for slab is 15mm.

H. Working out the quantity of concrete: -

By referring structural drawing, total quantity of concrete can worked out.

Advantages of working out the quantity are as under:-a. To know the volume of coarse aggregate, fine aggregate,

number of cement bags requires.b. To know the nearest variation in the volume of concrete

which may occur during casting due to few irregularities, such as

c. Adding Less aggregate during batchingd. Unequal depth of slab To prevent wastage of concrete To know the nearest expenditure required to cast the slab To employ the contractor to cast slab In piece work basis or On rate basis.

Since concrete of grade M20 is used for casting slab, the ratio is 1:1.5:3.

This prepared concrete is discharged in a pan of tower hoist, thus concrete is transported vertically up to the second floor from ground floor and then it is discharge.

Manual transportation of material. Vibration-needle vibrator. If depth of slab is maintained. Finishing. Curing of concrete by ponding for minimum 15 days.

I. Casting of slab

Slab surface after 12 hours

5. Equipment:-Major equipment required during and before casting of slab are as under:-

Cubical gauge box (Farma):- Volume of gauge box is 0.035m3. It is use to volume batching of fine aggregate and coarse aggregate

Bar bending keys-use to bend bars.

Transit mixture-use to

make concrete by thoroughly mixing sand, aggregate, cement and water in proportionate amount

Vertical hoist-use to lift the concrete vertically from ground floor to higher floors.

Niddle vibrator-use to penetrate into deep beam and results in better compaction.

Hook-use to bind reinforcement with binding wire.

6. WORKING OUT THE VOLUME OF CONCRETE: - Volume of concrete calculated by using structural drawing, floor plan and bar bend schedule of slab,

beam and column.

Total volume of concrete

Thus the total volume of concrete required for slab is 25.956m3. Therefore, adding 52% to get dry

volume=1.52×25.956=39.453m3. For M20 grade, volume of cement is=39.453/ (1+1.5+3)

=7.173m3.

Therefore, no. of .cement bags=7.173÷.034=205bags Volume of fine aggregate=7.173×1.5=10.759m3. Volume of coarse aggregate=7.173×3=21.519m3

total volume

SR.NO. MEMBERS VOLUME UNIT1 BEAMS-R 4.9868 CUB.MT.2 BEAMS-H 8.6064 CUB.MT.3 SLAB 9.2566 CUB.MT.4 BALCONY 1.1878 CUB.MT.5 COLUMN 1.9184 CUB.MT.

TOTAL 25.956 CUB.MT.

7. Activities to be carried out after casting of slab:-

A. Removing some part of formwork or centring:- 16-24 hours is the minimum period before striking

vertical formwork of columns, walls and beams. B. Inspection: - A simple inspection is carried out to see the quality of

concreting and appearance of finishing surface when formwork is removed. If any defect is detected such as :-

Honey combing, Rough surface due to segregation of concrete, etc. appear

on the surface on beam sides after hardening then it is repaired by applying Cement paste on that surface or Grouting.

C. Marking of centreline

It is done by taking the reference of column position at plinth level and transferring the point on the surface of slab at all four corners, so that position of column above the slab must be located exactly over the column below the slab.

The centre-to-centre distance between upcoming columns over slab must be marked as per centre line drawing.

Using centre line marking, dimension of column (B×D) can be located.

Diagonal check can also be obtained and can also be corrected, if found incorrect.

D. Ponding and Curing

small ponds of rectangular shape prepared on the hardened surface of slab throughout the surface area by using mortar prepared in a ratio of 1:8 to 1:10.

This rectangular pond after hardening is filled with water, thus curing the concrete.

This poor quality of mortar is so prepared so that it can be easily removed from the slab surface after curing.

E. Casting the starter before casting of column:-

Starters are the portion of column of depth 75-100mm approximately.

Wooden mould is of the size of column which is used to cast the starter and is placed over the located position of column by referring centreline.

Then the mould is filled with concrete of grade M20. After hardening concrete, mould is removed……………contd.

8. Conclusion

Industrial training has helped to understand the theoretical concepts of the various subjects such as

Foundation Engineering, Estimation and Costing, Concrete Technology, Building Construction and their relation with practical means. It has also helped me to understand the managerial part of

planning with respect to proper and timely execution of work, material management, etc. Industrial training develops a skill of observation, and a skill to understand the various problems faced at site and the way to overcome with this problems.

Since my training report in on the residential building, it has given me the opportunity to calculate the volume of concerte required to cast the slab which is a sure means of practical knowledge. It has also given me the idea about the importance of stepwise execution of work.

Thank you