Flyover construction

A PROJECT REPORT ON FLYOVER CONSTRUCTION AT

BIHAR RAJYA POOL NIRMAN NIGAM LTD.GOVT OF BIHAR

SUBMITTED BY:- SUBMITTED TO;-AKHILASH KUMAR DR.SHEETAL AGARWAL CIVIL ENGG.(VIIth sem.) ( HOD OF CIVIL ENGG.)ROLL NO:-12EAYCE005

DEPARTMENT OF CIVIL ENGINEERING ARYA COLLEGE OF ENGINEERING &RESEARCH CENTRE SP-40, RIICO INDUSTRIAL AREA, KUKAS, JAIPUR, RAJASTHAN RAJASTHAN TECHNICAL UNIVERSITY, KOTA

Company : BIHAR RAJYA POOL NIRMAN NIGAM LTD.

Project Name : FLYOVER CONSTRUCTION

Location : MITHAPUR FLYOVER TO CHIRAIYATAND

& CHIRAIYATAND TO GANDHI MAIDAN Estimated cost : 100 Cr.

PROJECT DETAILS

PILEAs we know PILE is a column (of reinforced concrete) which transfers the load of superstructure directly to the soil strata.The piling is necessary to make the foundation as well as soil strata reliable to withstand the load conditions more safely.Before installation of END BEARING PILE, settlement under Pile Load Test was observed in between 6-12mm which shows the green signal to install.NOTE- In pile foundation, 10% cement more is required.

PILE

PILE –CAPA thick concrete mat that rests on piles collectively to provide a suitable stable foundation is Pile Cap. It is 1.8m thick and 5.2m wide.

PILE –CAP

PIERA vertical supporting structure over pile cap is Pier Shaft. The thickness is provided according to drawings.NOTE-Shaft dimension is 1500mm x1500mm at Exhibition road site.

PIER

ABUTMENT & A.CAPAbutment are typically used where column lengths on multi-column piers will require larger column sizes due to slenderness. Abutment are also an option where stream flow could result in debris build-up between columns of a multicolumn.

ABUTMENT

PEDESTALPedestal is an independent support to bearings, over Pier/Abutment Caps. NOTE-• Pedestal dimension is 950mm

x850mm x250mm.• The number of Pedestal over a

Pier Cap is 4.• The number of Pedestal over a

Abutment Cap is Wall. 2 with a Dirt

PEDESTAL

BEARINGThe bearings used in the construction are Pot Bearings. Pot bearing is named so because bearing is confined in a steel pot.Although it has some specific characteristics which tend an engineer to use it. These are as-

• Negligible vertical deflection as only 0.06”.

• Uniform loading acceptability.• Minimal load eccentricity as up to

3% of the disc diameter.• Having least resistance in the

range of 0.01 to 0.022 radians.• Lower peak pressure on bearing

seats due to hydraulic design principle, characteristic load distribution curve is flatter.

• High horizontal load capacity.

BEARING

SEGMENTA flyover segment is the roadway surface of the flyover.

These segments have shuttering formwork made of high strength steel which are cast in casting yard.

SHUTTERING FORMWORK OF SEGMENTS

These precast units are installed through a Bridge Launcher Machine.

SEGMENTS INSTALLED BY LAUNCHER MACHINE

GLUING BETWEEN SEGMENTS After gluing, the segments are connected through strand bars (15.2mm dia.). The process is termed technically as “Threading”

STRAND BARS

NOTE-• There are 10 holes on each face of

the segment.• Each hole comprises of 19 bars of

15.2mm dia.• The overall threading of a span is

parabolic due to variation of hole’s position of segments lying over the span.

• After this post tensioning is done to make it a pre stress unit using tendons.

CRASH BARRIERThe barrier which checks errant vehicles from jumping outside from the flyover is called as Crash Barrier/Traffic Barrier.The width of Crash Barrier is 500mm.

FACIA PANELThe facia panel is the smallest unit of reinforced earth wall.

It is a precast unit containing bricks and concrete with covering.

REINFORCED EARTH WALLThe Reinforced Earth wall is made up of facia panels. These panels are arranged in the same way as of brick’s bonds. This Reinforced Earth Wall provides 25% more safety to the superstructure.

GEOGRIDGeogrid is a geopolythene material, used to provide the levelling of sand stratum at its level. There is a Hook embeded in panel connecting its two front wall’s hooks with Geogrid by a connecting rod in each hook.

SAND COMPACTION• Sand compaction is an important

work in flyover a ramp. • The sand is get self compacted by

sprinkling water over it.• The compactor machine compacts

with 8kN/m2 at the middle.• The sides are compacted with

1Kn/m2 by a baby roller or plate vibrator.

SAND COMPCTION

DIRT WALL /BALLAST WALLThe dirt wall is a wall which stands on the Abutment cap end to end apart from pedestals. This wall bears the load of ramp next to RE Wall on the abutment.NOTE- The end sides of the dirt wall should be matched properly with the ends of R E Wall and thus in the same way till crash barrier.

Thank you!

ANY QUERIES ?

Courtesy : Akhilesh Kumar