Girder’s Response under Integral Abutment Bridge

Abstract

From the past evaluation and trend in bridge engineering Integral abutment bridges are gaining more popularity than conventional bridges. Kalkaji Flyover Delhi is one of the recent examples of five span continuous deck IAB. Girders are directly joined with abutment/piers without any bearings. These girders play most important role in dead load of bridge. The present study is the analytical investigation of precast concrete girder used in IAB undergone to different loads. The software used for the analysis is Csi Bridge in which a bridge of width 22 metres having the slab thickness 0.3 metres is analysed. There are five longitudinal girders (I beam of 575 mm width and 250 mm thickness) provided across the bridge’s width spaced at 2.54 metres centre to centre from each other. The girder is subjected to dead load, thermal load, backfilling, dead load with thermal load and combination of loads. Through the finite element modelling, values for different parameters for different load cases are computed. The results of this study are showing that there is no effect of backfilling for hogging but on the other hand for sagging moment the value is 12.35 kN-m. Maximum value of bending moment is due to combination of loads. Stresses developed in deck slab at the bottom are highest due to thermal loads and lowest due to backfilling. On the top of deck the stress values are highest for combination of loads. Deadload can be reduced if the Steel Plate girder is used that’s the practical implementation in integral abutment bridges.