Parameters of Pre-Stressed Box Girder Bridge under Different Radius of Curvature

Dr Rajan Suwal , Deepika Sharma

This research, it is primarily intended to assess parametric study of pre-stressed Box-Girder bridges. Radius of Curvature was varied in 50m span bridge in horizontal direction only. All the models are subjected to self-weight and moving load of IRC class 70R vehicle [3]. For this research, a three dimensional finite element (FE) model of two lane simply supported Box Girder Bridge made up of pre-stressed concrete has been developed using commercial software SAP 2000 version 14.0. Modal analysis has been carried out to obtain the mode shapes and various vibration properties such as fundamental time period and frequencies. For acceleration time history analysis Gorkha Earthquake has been used. From modal analysis the longitudinal stress at top and bottom of cross sections, bending moment, torsion, deflection and fundamental frequency are calculated. The responses of a curved bridges in comparison straight bridge are recorded. The ratio of responses is represented by a parameter. From the responses linear equation has been generated for torsion, bending moment, and deflection. Increase in Bending Moment, Torsion, deflection and stresses due to curvature can be represented by multiplication factor, ratio of maximum response of curved bridge to that of straight bridge from moving load analysis, within reasonable accuracy which can be used in preliminary design.