Seismic analysis of cable stayed bridge with different pylon shapes

Abstract

Cable stayed bridge are the most flexible bridge then other bridges and getting popularity because it represent optimum solution for ever expanding range of span and aesthetics . This work focused on the effect of shape of pylon on the transverse seismic response of cable stayed bridge for that the dimension of deck and other parameters are kept constant only the shape of the tower is varied, such as H-shape, inverted Y shape, inverted Y shape with lower diamond, A shape, A shape with lower diamond. This work also gives the essential information of the fundamental vibration mode which is based on mechanical and geometrical property of the structure. Which is required in early stage of design until optimum solution is not made. Five tower shapes of the lateral cable-system layouts are to be considered. The 3D model of the cable stayed bridge is generated in SAP-2000(VER.18) and it is analyzed seismically Bhuj 2001, Earthquake India. The response of bridge is studied in the terms of natural time period, displacement in transverse direction of pylon along the height, base reaction. This study reveals that the shape of the pylon play an important role in seismic response of cable stayed bridge. Inverted Y shape pylon is better in resisting when earth quake strikes from transverse direction.