In order to simulate the zonal disintegration phenomenon of rock mass around deep tunnel, this study proposes two types of three-dimensional strain-softening heterogeneous mechanical models, i.e., loading model and unloading model. Numerical results show that under these two conditions, the phenomenon of isolated annular regions with higher or lower shear strain increments is observed in planes orthogonal to the tunnel axis. In addition, the results based on the unloading model are closer to the actual situations than that based on the loading model. The zonal disintegration phenomenon is believed to be formed by several spatial cone-shape shear bands.