Mechanical and Numerical Simulation on Weathered Argillaceous Siltstone under Cyclic Loading

Secondary lining cracking always occurs in existing tunnels when the tunnel passes through the weathered argillaceous siltstone layer, which seriously affects the safety of the tunnel. In order to study the mechanical properties of weathered argillaceous siltstone and the cracking law of the secondary lining, this study analyzes the relationship of accumulative plastic strain between the dynamic stress amplitude and static deviator stress, as well as the cracking law of the secondary lining of the sample. The results show that under cyclic loading, there are obvious accumulative plastic strain in weathered argillaceous siltstone; the bearing capacity of the secondary lining structure at the biased part shows an evident increase than that of others with cracking generating faster. The research results provide a reference for the safety and operation of the tunnel that runs through the weathered argillaceous siltstone layer.