Aseismic Experimental Research on Safety-Belt System of a Low-Gravity-Center Cable-Stayed Bridge

The seismic performance of low-gravity-center cable-stayed bridges is influenced by their structural system. This paper introduces a novel anti-seismic structural system designed to enhance the earthquake resistance of low-gravity-center cable-stayed bridges while reducing secondary internal forces during operation. A total of 47 groups of shaking table tests were conducted, considering four types of seismic waves and acceleration levels. In the shaking table tests, a safety-belt device was constructed and integrated into a scale model of a low-gravity-center cable-stayed bridge. The anti-seismic performance of the safety-belt system was validated by comparing the shaking table test results of the asymmetric restraint system and floating system reported in previous studies. The experimental findings revealed that the strain response at the tower bottom and the displacement response at the tower top were lower in the safety-belt system model. The safety-belt system shows potential for application in low-gravity-center cable-stayed bridges to reduce earthquake impacts. Furthermore, this study elucidates the damage mechanism of low-gravity-center cable-stayed bridges equipped with the safety-belt system under seismic loading, providing references for optimizing the anti-seismic design of such bridges.