Development and experimental investigation of a novel self-centring friction rope device for continuous bridges

Abstract

This paper proposes a novel self-centring friction rope device (Sc-FRD) for improving the seismic isolation and re-centring effect of continuous bridges. The Sc-FRD is designed to provide energy dissipation and re-centring functions and works in conjunction with typical sliding bearings to separate vertical support. The Sc-FRD isolated system allows function separation, with sliding bearings supporting vertical loads, friction rope dampers (FRDs) dissipating seismic energy, and self-centring springs providing re-centring forces. Firstly, a constitutive model of the Sc-FRD was developed by theoretical analysis, and the mechanical properties of the FRD were studied through quasi-static testing. Then, a 1/30-scale, three-span continuous bridge model was constructed and tested on the shake table to investigate the seismic performance of the Sc-FRD isolated system. Finally, the software ANSYS was employed for an effective simulation of the shake-table test. The test results showed that the Sc-FRD isolated system performed well in seismic isolation and energy dissipation. It could effectively reduce the fixed pier’s earthquake responses and restrain the isolator’s residual displacements within an acceptable range. Furthermore, the Sc-FRD’s main parameters and ground motion characteristics greatly influenced the residual displacement of the bridge isolation system, with the coda stage of ground motions playing a critical role in the superstructure’s re-centring.