Aseismic performances of constrained damping lining structures made of rubber-sand-concrete

Abstract

Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering structures. In this study, a constrained damping structure for underground tunnel lining, using a rubber-sand-concrete (RSC) as the aseismic material, is proposed. The aseismic performances of constrained damping structure were investigated by a series of hammer impact tests. The damping layer thickness and shape effects on the aseismic performance such as effective duration and acceleration amplitude of time-domain analysis, composite loss factor and damping ratio of the transfer function analysis, and total vibration level of octave spectrum analysis were discussed. The hammer impact tests revealed that the relationship between the aseismic performance and damping layer thickness was not linear, and that the hollow damping layer had a better aseismic performance than the flat damping layer one. The aseismic performances of constrained damping structure under different seismicity magnitudes and geological conditions were investigated. The effects of the peak ground acceleration (PGA) and tunnel overburden depth on the aseismic performances such as the maximum principal stress and equivalent plastic strain (PEEQ) were discussed. The numerical results show the constrained damping structure proposed in this paper has a good aseismic performance, with PGA in the range (0.2–1.2)g and tunnel overburden depth in the range of 0–300 m.