New Solution of Rock Resistant Coefficients Based on the Mogi-Coulomb Failure Criterion
(1 College of Architecture, Chang'an University, Xi'an 710061; 2 Department of Civil Engineering and Architecture, Nanchang Institute of Technology, Nanchang 330099)
Abstract：
The rock resistant coefficient is one of the important parameters in the support design of underground structures such as hydraulic tunnels. Based on the ideal elastic-plastic material model and the Mogi-Coulomb failure criterion, which considers the role that intermediate principal stress plays in increasing strength of the surrounding rock, an analytical solution of stress and displacement of the surrounding rock around a deep buried circular tunnel is derived, and a new solution for the rock elastic-plastic resistant coefficient is obtained. Lastly, the effects on rock strength parameters are studied after the comparison and verification of all the solutions. The results show that the new solution for the rock resistant coefficient based on the Mogi-Coulomb failure criterion is between the solutions of Matsuoka-Nakai (SMP) failure criterion and the Lade-Duncan failure criterion, with little differences; as the solution of the Mohr-Coulomb failure criterion is obviously smaller than the other ones, the consideration of intermediate principal stress could give full play to the load sharing capability of the surrounding rock; and the cohe? sion and inner friction angle have great influence on the rock resistant coefficient, and the influence of the inner friction angle is more obvious.
ZHANG Chang-Guang- 1 Zeng-Kai-Hua- 2
.New Solution of Rock Resistant Coefficients Based on the Mogi-Coulomb Failure Criterion[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(5): 31-34
2016, Vol. 53 