industrial training of flyover construction

• The Public Works Department has a glorious history in the development of the state since pre independence. The department is entrusted with construction, maintenance of Roads, Bridges and Govt. buildings.

• It also acts as Technical Advisor to the State Government in these matters. Initially, Irrigation, Public Health engineering were units of PWD.

• Since the inception of the Department, it has strived through its continuous quest for excellence and putting milestones in the feat of Engineering.

Flyover: - It is a bridge that carries one road or railway line above another either with or without subsidiary roads, for communication between the two.

WHAT IS FLYOVER BRIDGE

REASON BEHIND GOING FOR A FLYOVER

• As the traffic on the road goes on increasing and we don’t have any space left in both the dimensions, then the only option left will be to go to the third dimension and that is done through flyover construction.

• The six- lane corridor, which is 1.6 km long, on Ring Road is expected to cut down commuting time as it will bypass three major traffic jam intersections at Ashok Vihar, Shalimar Bagh and Keshav Puram

TYPE OF FLYOVER BRIDGE

Road Crossing

Simple Flyover Cloverleaf Junction

Railway Crossing

MAJOR COMPONENTS OF FLYOVER

• Pile • Pile cap • Piers & Abutments• BridgeDeck• Pedestal• Bearing • Parapets (Bridge Railings)

COMPONENTS OF FLYOVER

FOUNDATION

Since the bridge has to carry a big live load and its dead weight is also very large so we cannot go for simple foundation but pile foundation. Pile foundation is one type of deep foundation. It is used where the good soil is at higher depth (10 or 15m) or soil having low bearing capacity. Pile is also used for tall structures. In pile foundation the load coming from the super structure is taken by pile cap and equally distributed in no of piles, pile transfers this load into the soil.

DESIGN OF FLYOVER

All roads, flyovers, etc are designed solely to accommodate the heaviest and tallest vehicle: the fully loaded truck, thus resulting in a gross over design for cars. The slab of a flyover is designed to withstand the 20 tonne weight, (dynamic load) of a fully loaded truck. This results in a slab with box girders that are about 2-3metres deep. Similarly the clear height of the flyover slab is based on the requisite 7-9metres clearance for a truck. The finished slab of the flyover is at +9-12metres. The slope of the flyover ramp is also calculated on the basis of a 1:20 gradient, on the basis of a truck. However, a slope of 1:10 would provide comfortable access for cars. The cost saving alone in the embankments would be considerable. Similarly, by factoring segregation of traffic into design for each aspect, there would be enormous design optimisation and concomitant cost saving.

PLAN SHEET

SALIENT FEATURES

Project Estimated Cost 257cr

Project Total Cost 150cr

Agency PWD

Consultant SIMPLEX PVT.LTD

Date of commencement JUNE,2013

Stipulated date of completion 10 NOV,2015

PHYSICAL FEATURES

Total Length of the Flyover 1.6km

Width of Flyover 21m

Length Of Column 6.5m

Length of Pile 33m

Spine 6.1m

Wing 9.1m

No. of Spans 14

No. of Piles 303

No. of Pile caps 31

No. of Pier and Pier caps 31

Spine Casting 368

Wing Casting 736

Segment Erection 30

Wing Erection 30*2 span

COMPLETE WORK STATUS OF PREMBARI AZADPUR FLYOVER

SEGMENT

A flyover segment is the roadway surface of the flyover.

These precast units are installed through a Bridge Launcher Machine

PRE-STRESSED CONCRETE

• Prestressed concrete is the one in which there have been introduced internal stresses of such magnitude and distribution that the stresses resulting from the external load are counter balanced to a desired degree.

• Pre stressing can be accomplished in three ways: pre-tensioned concrete, and bonded or unbonded post-tensioned concrete.

PRE-TENSIONING

• In this method of prestressing in which tendons are stretched /tensioned before the placement of concrete.

• Prestress is imparted to concrete through bond between steel and structure.

POST-TENSIONING

• In this method of pre stressing tension is applied to tendons after the concrete has been set and hardened. Here the pre-stress is imparted to concrete through bearing.

Prestress Post Tension Anchor Prestressing Equipments

ROAD WORK

• 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.

SOME PRECAUTIONS DURING INDUSTRIAL TRAINING

• Always wear a good quality helmet on the site.

• Always wear shoes on the site.

• Wear safety belts if required.

• Safety nets should be provided wherever it is necessary

AZADPUR FLYOVER

THANK YOU