Date of Publication :22nd March 2017

Abstract: Reinforced concrete bridges with different types of deck slab have been widely used for both road and railway bridges. The most common type is the slab deck used for short span bridges. For medium span in the ranges of 12 to 25 m T- Girder and slab deck is widely used. In the case of T Girder and deck slab type, the slab span in two directions since it is cast integrally with main girder and cross girder. The deck slab is generally designed for either by 70 R loading or class AA Tracked wheel loading. IRC recommends bridge designed for class AA loading should also be checked for IRC class A loading. However in conventional analysis many of the important considerations are ignored by the various designers, which proved out to be somewhat unrealistic during the pragmatic conditions. For an assessment of the load carrying capacity of a bridge, one needs to know the maximum bending moment and the shear force included in the beams or girders of the bridge by vehicular loads. These maximum design load effect can be calculated by the conventional method such as Courbon’s method. The main objective of study is to analyse super structure for IRC Class AA loading (Tracked vehicle) and IRC Class A loading to compute the values of bending moment, shear force and deflection for span range from 16 to 24 m. The analysis of super structure of different sections and spans is carried out by Courbon’s method using MS Excel and by using STAAD.pro software. The bending moment and shear force results obtained by STAAD.pro were less up to 18 m span when compared to results obtained by MS Excel and vice-versa as the span increased. The safe design section is obtained by deflection criteria.

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