Shear lag in typical box-girder bridge, Civil Engineering

Assignment Help:

Shear lag in typical box-girder bridge

For multiple-cell box girders, there are normally two arrangements. First one is that independent cells are connected by their top flanges only while the other one is that the cells are connected both at bottom and top flanges. From structural point of view, it's recommended to adopt the second arrangement. For the case of cells associated by top flanges only, their flanges are heavily stressed in transverse direction owing to flexure that can't be effectively distributed across the cross section.

In structural analysis of bridges shear lag have to be considered in design in some situations. Shear lag occurs when some parts of cross section aren't directly connected. For a box-girder bridgenot all parts of flanges are joined directly to webs so that connected part becomes highly stressed whereas unconnected flanges aren't fully stressed. Particularly for wide flanges of box-girder bridges axial loads are transferred by shear from webs to flanges that result in distortion in their planes. Therefore plane sections don't stay plane and stress distribution in the flanges aren't uniform. Furthermore there is a tendency for longitudinal in-plane displacements of bride deck away from web/flange connection to lag behind those parts of bridge in close vicinity to web/flange connection.

The effect of shear lag causes longitudinal stress at flange/web connection to be higher than mean stress across the flange. Thus the effect of shear lag has to be catered for in the design of box-girder bridges specifically for those with wide flanges.


Related Discussions:- Shear lag in typical box-girder bridge

Determine the ruthann graphical method, A retaining wall with a vertical ba...

A retaining wall with a vertical back 5 m high supports cohesion less backfill of unit weight of 19 kN/m 3 . The upper surface of the backfill rises at an angle of 10° with the hor

Differentiate between concrete and tendons, Differentiate between concrete ...

Differentiate between concrete and tendons In the case of pre-tensioned concrete members, the transfer of prestress takes place due to the bond between concrete and tendons. In

Determine the limit state of serviceability, Determine the Limit State of S...

Determine the Limit State of Serviceability Cracking Cracking of concrete should not affect the appearance or durability of the structure. The criteria of limit state of cracki

What is the safe bearing capacity of wide strip footing, A loading test was...

A loading test was conducted with a 300 mm square plate at depth of 1 m under the ground surface in pure clay deposit. The water table is situated at a depth of 4 m below the groun

Main and key benefits of piers constructed monolithically, What are main a...

What are main and key benefits of piers constructed monolithically with bridge deck over usage of bearings?

Build of a cmplete home, how can we build a complete home on an area of 500...

how can we build a complete home on an area of 500 meter squares with garden and house and a garage

Illustrate the types of prestressing, Illustrate the types of prestressing ...

Illustrate the types of prestressing we can classify prestressing into two forms  : (a)  longitudinal prestressing, and (b)  circular prestressing.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd