Shaking Table Model Test of Loess Tunnel Structure under Rainfall

摘要

A large number of loess tunnels are being built or have been put into operation due to the vigorous development of highways and railways. Due to the broken, porous and multiphase of loess microstructure, the loess will lose its strength rapidly under the loading conditions of rainfall and dynamic, while the shaking table test can be used to simulate this dynamic process much better. Based on the shaking table model of 1/40 loess tunnel and considering the adverse conditions of El-Centro bidirectional seismic wave and rainfall, the seismic response law of loess tunnel is studied in this paper; the damping effect of the loess tunnel structure is discussed by setting the damping layer. The results show that under the action of rainfall and earthquake, the damage of surrounding rock structure precedes that of lining structure; the acceleration of the lining structure changes little under different rainfall conditions, but the strain tends to increase; under the cumulative effect of ground motion, the failure time of surrounding rock structure appears early in the case of heavy rainfall, and the width and depth of crack finally formed are also larger; the setting of damping layer can obviously reduce the strain under different rainfall.