Dynamic damage evaluation of lining across the main sliding surface reinforced with multi-anchor round piles under different seismic sequences

Abstract

Abstract To study the dynamic damage effect of lining across the main-sliding surface reinforced with multi-anchor round piles under different seismic sequences, shaking table test is used for the first time to design two loading sequences of "foreshock-main shock" and "mainshock-aftershock". Based on acceleration, the seismic performance evaluation factor (SPEC) and seismic effect coefficient (Sec) of reinforced lining are proposed. Based on dynamic strain, a calculation method of shear force (Sf) and bending moment (Mb) of multi-anchor round piles is proposed, and the distribution characteristics are given. The evaluation index of reinforcement effect evaluation coefficient (REEC) of reinforced lining is put forward. The results show that the acceleration of the main-aftershock sequence to the multi-anchor round piles is greater than that of the foreshock-main shock sequence. The Sf of pile presents inverted "S" type distribution, while the Mb presents "S" type distribution. Compared with the unoptimized multi-anchor round piles, the seismic effect of Sec and REEC can reach 3.04%-18.96% and 120%-180% respectively. The seismic effect of anchor head optimization is related to seismic sequence, and it is more suitable for seismic structure design of foreshock-main shock sequence. It has great popularization value in tunnel-landslide engineering treatment in high intensity area.