Effect of Skewness on Live Load Distribution in Webs of Concrete Box-Girder Bridges

Abstract

The aim of the present paper is to study the effect of skewness on distribution of live load among the webs of the horizontally curved concrete box-girder bridges. In this paper, a 27.4 m long simply supported RC box-girder bridge has been considered to investigate the influence of skewness on box-girder with various curvatures. To this end, the central curvature angle of the bridge has been varied from 0° to 48° at an interval of 12° and the skew angle is swept from 0° to 50° at an interval of 10°. Using the three-dimensional Finite element analysis software CsiBridge, maximum vertical deflection under the webs of box-girder have been determined due to the IRC specified Class-70R tracked vehicular LL moving over the bridge at constant speed at maximum eccentricity specified by Indian Road Congress. Assuming the linear elastic behavior of the bridge, the live load has been distributed among the webs in the proportion of vertical deflections. The study revealed that the live load distribution among the webs is significantly affected by the skewness in conjunction with curvature. The results indicate that with increase in skewness, live load transferred to inner web decreases for almost all the curvature angles