5 - precast structures in india - sthaladipti saha

Precast

buildings in

India

by

Sthaladipti Saha

Chief Engineering Manager

Larsen & Toubro

Larsen & Toubro Limited,

ECC Division,

Chennai, India

Introduction…

Precast concrete construction in India

With the advent of precast concrete construction in India

post independence, L&T has used this method of

construction to gain a stronghold in the construction sector.

The methodology followed was the

setting up of a site prefabrication

yard close to the project site for ease

of transportation and use.

Gantry Casting yard

Introduction…

L&T‟s foray into precast construction . . .

• Roof elements

• Folded plate

• Truss

• Shell

• Silo

• Waffle slab

• Pipe rack

• Special structures

• Wall panels

• Miscellaneous

Tilting mould

Roof elements…

Folded plate

Structural steel arrangement

Side shutter reinforcement Curing

Mould

Roof elements…

Folded plate

Folded plates stacked in yard Loaded on trailer

Demoulding Temporary ties

Roof elements…

Folded plate

Erected using cranes

Sl.N

o Description Unit Qty

Qty /

Sq.m #

1 Concrete M40 Cum 6.20 0.103

2 Mould assembly

& demould Sq.m 130 2.17

3 Reinforcement Kg 1300 21.7

# Quantity per Sqm of Roof (plan) area

Techno-economic indices

Roof elements . . .

Folded plate

• Used as large span roofing

elements

• Efficient from viewpoint of

material consumption

24m span precast concrete folded plate

with north light glazing on one side for

MICO , Bengaluru

24m span precast concrete folded plate at

Pearl distilleries, Ongole

“V” shaped folded plate - 36m long, 6.5m

wide & 2.35m height at Ocean Engineering

Centre – IIT Chennai

Roof elements . . .

Folded plate

Gabriel India Limited at Pune

Perfect Circle Victor at Pune

Roof elements . . .

40m span precast concrete A-frame

supporting trussed purlins – Silo for SPIC at

Tuticorin

38m span precast trough slab A-

frame silo – State fertiliser

manufacturing Corporation,

Colombo

Truss

Truss Roof elements . . .

30m span precast concrete roof truss in

single piece as roof element for Food grain

godown at Madras port trust

20m span precast concrete arch shaped

truss and slabs as roofing system for

Tamilnadu minerals at Chennai

Truss Roof elements . . .

48m span precast

concrete truss – L&T

cements, Awarpur

Truss Roof elements . . .

27.7m precast concrete roof truss –

Foundry for Grindwell Norton at

Renigunta

Truss

Roof elements . . .

18m span diamond shaped precast concrete

truss with rafters and purlins as north light roof

system at EWL, Chennai

16m span precast concrete truss

supporting 13m span precast prestressed

concrete slabs as roofing systems for

indoor switchyard at Tuticorin

13.5m span north light precast

concrete portal during erection

– L&T McNeil at Chennai

22m precast concrete portals

with 8m span precast purlin –

Heavy Engineering Workshop

at L&T Hazira

Truss

Roof elements . . .

Shell Roof elements . . .

Erection of HP shell – Finishing shop

at L&T Bengaluru works

HP shell roof – L&T Bengaluru works

Silo

43.5m precast

prestressed concrete

truss (in 3 pieces)

and slabs as roof for

silo at Kakinada

Roof elements . . .

Silo

Roof elements . . .

55m span urea silo at IGFL Jagdishpur

Cyber park, Hyderabad

Waffle slab Roof elements . . .

Convention center, ECC

HQ campus

Columns & Beams. . .

• 15m precast columns

• Weight of column – 25MT

• Precast beams at gable end

ITC Badrachalam

Erection sequence

Pipe rack. . .

Erection sequence

Pipe rack. . .

Erection sequence

Pipe rack. . .

Erection sequence

Pipe rack. . .

Pipe rack. . .

Curing

Casting

Pipe rack. . .

Erection

Pipe rack. . .

Pipe rack. . .

Precast concrete trestles used for pipe rack structure at

Kothari caustic soda project at Manali

Panipat Naphtha cracker project

Special structures . . .

• Size – 24 x 6 x 3m

• 160mm to 250mm c/s

• Weight – 120MT

• No. of elements - 234

Bengaluru International Airport

Wall panels. . .

Bengaluru International Airport

Wall panels. . .

Mumbai International Airport

Wall panels. . .

Cognizant at MEPZ, Chennai

Beer bottle finish on the outside surface of

precast wall panel at L&T Bengaluru works

14m high 2.5m wide precast concrete

grooved wall panel with precast concrete

gutter for the assembly shop of L&T Poclain

– Bengaluru

Wall panels. . .

School rooms at Gujarat

In stacking yard

In transit

• 6000 school rooms

• Each of 54 sq.m. BUA

Assembled school room

Wall panels. . .

Curing tank

Compound wall. . .

Bengaluru International Airport Delhi International Airport

Miscellaneous. . .

Precast concrete water tower with

beer bottle finish on the outside

surface at L&T Bengaluru works

15m span conveyor galleries in

precast concrete at Awarpur

cement works

TISCO housing, Jamshedpur South city, Bengaluru

Miscellaneous. . . Stadiums

Precast bleachers and raker

beams in Qatar football stadiums

Precast roof element

and gallery units in

Jawaharlal Nehru

Stadium at Chennai

– built in 260 days

Elliptical roof made of 120 V-type folded plates of 40m span –

Kanteerava indoor stadium in Bengaluru

Miscellaneous. . .

EDRC building, ECC HQ campus

Precast „L‟

shaped duct

units in staking

yard

Delhi International Airport

• Precast element size – 2.0m X 1.5m

• No of Pieces – 1200 Pieces of 1.2m length

• 2.4 Kms completed in 4 months

Miscellaneous. . .

Box culvert under

pavements

Delhi International Airport

Precast pipes

Delhi International Airport

Precast drains

Miscellaneous. . .

Delhi International Airport

Precast baggage handling tunnel

Miscellaneous. . .

• Precast Tunnel Element size

• 4.43m X 2.8m of 1.2m length

• Precast tunnel length – 700m

Conclusion…

Precast concrete construction in India – the future . . .

Increase in urbanization and consequent shortage of skilled

labor and better infrastructure will require construction to

focus more on industrialized methods of construction like

prefabrication.

Move from site Prefabrication to Plant prefabrication . This

will lead to speed, economy and reduce the need for skilled

manpower.

L&T is setting up a Hollow core factory inline with the

changing scenario.

Thank you