PRESENTATION about CONSTRUCTION TECHNIQUES

ofCABLE STAYED BRIDGE on RIVER

TAPI joining ATHWALINES & ADAJAN

by1. Mahesh Kumar Patel (u10ce048) 5.Rohit S. Patel (u10ce052)2. Rishabh Ranka (u10ce049) 6.Suraj Prakash (u10ce053)3. Abhinandan Kumar Abhay (u10ce050) 7. Parth Parmar (u10ce054)4. Sanjay Kumar (u10ce051) 8. Yogesh Mehta (u10ce055)

Guided by1. Dr. R. A. Christian2. Shri Bhavin Tandel

BRIDGE PROFILE1. Detail of cable stayed portion

• Length : 300 m• Width : 23.30 m• Area : 7050 sq m• Pylon : 2 nos. 35 m height

2. Total Length of bridge : 917.945 m3. Carriage Way : 7.50 m + 7.50 m 

(Two Lane up & Two Lane Down)4. Footpath : 2 m (both side)

5. Type of Foundation : Pile Foundation6. Sub Structure : R.C.C. Pier7. Super Structure : Segmental Multi cell Box

Girder/ PSC Box Girder / Solid Slab type

SUB STRUCTURE CONSTRUCTION

• A cofferdam is a structure that retains water and soil that allows the enclosed area to be pumped out and excavated dry.

• Cofferdams are commonly used for construction of bridge piers and other support structures built within water.

• Cofferdams walls are usually formed from sheet piles that are supported by walls and internal braces, and cross braces.

• Cofferdams are typically dismantled after permanent work is completed

• Since cofferdams are usually constructed within water, the sheet piles are installed using preconstructed templates that permit the correct positioning of each sheet pile from a barge.

COFFERDAM

COFFER DAM CONSTRUCTION• Step 1: Erect Bracing Frame• Step 2: Drive Steel Sheet Pilings• Step 3: Excavate Inside• Step 4: Prepare Interior bed for tremie concrete seal - Driving Piles - Placing rock fill• Step 5: Place tremie concrete seal to create water tight

seal• Step 6: Dewater

Steel sheet piles

CONSTRUCTION OF RIVER PILE

• Piling starts with construction of rolled sheet piles with help of steel sheets.

Rolled steel piles are driven in the river bed with the help of hammer.

This hammer works with the help of winch machine.

A frame known as “A-FRAME” is attached to the winch machine to drive the

pile attached with string.

Steel Sheets

Rolled Steel Sheets

Winch Machine

The string moves to and fro on the winch machine and it helps to drive the

pile down the river bed.

After driving the pile down the river bed, the use for chisel and barrel

pump starts.

Chisel is construction equipment which cuts the soil by hammering it.

A slurry of sand is created.

This slurry is then removed by the barrel pump.

Both the chisel and barrel pump are also operated by the winch machine

and A-frame.

Construction Of River Pile

Top view of a driven pile

A – frame with winch machine

A chisel under use

Removed liners of concreted piles

CONCRETING OF PILES After removing the slurry the water inside the pile is kept as it is.

On completion of the borehole, the reinforcement is placed with

suitable spacers to locate it centrally in the pile shaft.

Tremie method of concreting is employed when casting is done

under water .

By using a self-compacting concrete mix, it is not necessary to

vibrate the concrete in the borehole during casting.

As the concrete goes inside the pile, the water being lighter

itself starts coming out the pile from the top.

Figure Showing Concreting Of Pile

SUPERSTRUCTURE SELF CLIMBING FORM CONSTRUCTION• For the construction of R.C.C. piers the technique used

was self climbing form construction.• In which a special type of formwork for vertical concrete

structures that rises with the construction process. • It allows the reuse of the same formwork over and over

and over for identical (or very similar) sections.• It can also enable very large concrete structures to be

constructed in one single pour thus creating seamless structures with enhanced strength and visual appearance, as well as reducing construction times and material costs.

SUPERSTRUCTURESegmental Box girder / Pre Stressed Concrete Box

girder / Solid slab.• For the cable stayed portion segmental box girders/

PSC box girders were used which were casted using form travelers.

• The technique used for this was cast in place balanced cantilever method.

CAST IN-PLACE BALANCED CANTILEVER

• Each pair of segment should be built on both side of a pier at the same time to control the negative moment in cantilever.

• In this method two segments should be cast which will follow post-tensioned.

• The most advantage of using this method especially in urban areas refers to its characteristic that it does not need any temporary shoring. Additionally it can be used for irregular and long span lengths with few repetitions.

PYLON CONSTRUCTION

SUMMARY:

• Foundation(River piling) and Sub-structure(Piers

and pier cap) works are completed.

• Approaches from both the end is over.

• Box Girders casting are in full swing.

• Pylon erection is in progress.

• Cable erection and deck slab construction are yet

to commence.

THANKS