Finite Element Analysis on the Mechanical Performance of a Novel Modular Assembled Cable Bridge

This study proposes and investigates a modular assembled steel-UHPC composite cable bridge consisting of upper prefabricated UHPC ducts and a steel truss underneath. Finite element (FE) analysis is conducted to investigate the mechanical performance of the medium-span (L=36m) cable bridge under service-loading conditions. The FE results indicate that under combined action of vertical and horizontal loads, the tensile damage in the UHPC ducts reaches approximately 10%, mainly concentrated near the end-support sections. The peak stress in the steel truss is far below its yield strength. The peak vertical displacement of the bridge is approximately L/225, below allowable limit of L/150, and the peak horizontal displacement is negligible. A parametric analysis is performed for web sections in the midspan and end of the cable bridge. Results show that the peak stress located at the lower chord increases with larger midspan web section. The increase in the midspan web section triggered a stress redistribution in the end webs and, consequently, a rise in the peak stress under the same load case; the peak vertical displacement decreases while the horizontal displacement exhibits marginal change. Considering the structural performance and economic efficiency, the web sections in the end may be appropriately reduced.