Nonlinear Progressive Failure Analysis of Surrounding Rock System Based on Similarity Theory

Nonlinear progressive failure study of surrounding rock is important for the stability analysis of underground engineering projects. Taking a deep-buried tunnel in Chongqing as an example, a three dimensional(3-D) physical model was established based on similarity theory. To satisfy similarity requirement of physical mechanical properties, such as elastic modulus, compressive strength and Poisson ratio, physical model materials were developed. Using full inner-spy photograph technology, the deformation and failure process of rock were studied under the situation of independent and combined action of anchor, shotcrete and reinforcing mesh. Based on experimental results, the interaction mechanism between rock and support structure under high stress was investigated.