摘要

Given the ineffective anchorage of the middle tower, a triple-tower suspension bridge shows a different mechanical behavior when compared with a traditional suspension bridge. Accordingly, this work investigates the mechanical performance of triple-tower suspension bridges. First, theoretical analysis was performed while considering the top displacement of the side tower and the stiffness of the middle tower. And the analytical solutions to live load of cable force, girder deflection, and anti-slip coefficient between the cable and saddle were obtained. Second, finite element models were established to perform a parametric analysis on tower stiffness, sag-span ratio, and side-main span ratio. These parameters influence the mechanical behaviors of bridges in different ways, and determining these parameters at the conceptual design stage should fulfill the requirements of mechanical performance of these structures while comprehensively considering their economic performance.