Study on the settlement law of tunnel in diatomite stratum based on Strain Softening model

Nowadays, there is no precedent for building a high-speed railway in diatomite area. Due to the complex structure and poor mechanical properties of as well lack relevant engineering experience, more attention has been paid proper constitutive model tunnel layer using numerical calculation method, while traditional Elastoplastic most used yet. Therefore, relying on Feifengshan tunnel, through FLAC3D software on-site monitoring, analysis settlement law about tunnelling stratum carried out based different models. The research results show that obvious strain-softening characteristics. calculated surface vault Strain Softening was greater than Mohr Coulomb model. When compared with monitoring data, it found would accurately better applicability above-mentioned may provide some references construction design tunnels similar strata future.