Study on parametric behaviour of single cell box girder under different radius of
curvature

Abstract

Bangalore metropolis, the silicon valley of India, has experienced phenomenal growth in population in the last two decades. So, to meet the traffic demands, Metro Rail Transport started. Bangalore Metro Rail Corporation; is constructing some phase of Metro Rail to be of elevated one. There are different structural elements for a typical box girder bridge. The present study focus on the parametric study of single cell box girder bridges curved in plan. For the purpose of the parametric study, five box girder bridge models with constant span length and varying curvature. In order to validate the finite element modelling method, an example of box girder bridge is selected from literature to conduct a validation study. The example box girder is modelled and analysed in SAP 2000 and the responses are found to be fairly matching with the results reported in literature. For the purpose of the parametric study, the five box girder bridges are modelled in SAP2000. The span length , cross-section and material property remains unchanged. The only parameter that changes is the radius of curvature. The cross section of the superstructure of the box girder bridge consists of single cell box. The curvature of the bridges varies only in horizontal direction. All the models are subjected to self weight and moving load of IRC class A tracked vehicle. A static analysis for dead load and moving load, and a modal analysis are performed. The longitudinal stress at top and bottom of cross sections, bending moment, torsion, deflection and fundamental frequency are recorded. The responses of a box girder bridge curved in plan are compared with that of a straight bridge. The ratio of responses is expressed in terms of a parameter. From the responses it is found that; the parameters like torsion, bending moment, and deflection is increasing as curvature of the bridges increase.