Research Article

A New Unified Solution for Circular Tunnel Based on a Four-Stage Constitutive Model considering the Intermediate Principal Stress

Table 4

The post-peak failure radii and surface displacement when .

ModelTransformation

EPM1.1651.0001.0001.357
EPSDM1.3361.2951.1221.786
ESM1.4181.4181.2182.010
EPBM1.5401.4921.4922.371
EBM1.6021.6021.6022.565