Study on Mechanical Behavior and Failure Network of Deep Roadway under Different Lateral Pressure Coefficients

Abstract The failure and instability of roadway is a main disaster with the highest frequency in coal mines. The development of surrounding rock control technology is an important way to ensure mine safety. In order to obtain the failure characteristics of surrounding rock and optimize the support method of the roadway, the numerical simulation and physical simulation were used to investigate the mechanical behavior of deep roadway under different lateral pressure coefficients. The evolution mechanism of meso tensile-shear cracks in excavation damaged zone (EDZ) were deeply revealed. The results show that the shear bands which are basically in the form of sliding spiral extends from the two sidewalls to the roof and floor with the increase of lateral pressure coefficient, and develop to the deep surrounding rock. The “crescent-shaped” tensile failure zones generate in the roof and floor when λ < 1, and gradually decrease with the increase of horizontal stress. When λ = 1, the failure pattern around the arch and right angle sides are different influenced by the shape of different side. Under the special stress environment of high deviatoric stress, the pattern of plastic zone will lead to butterfly-like failure mode induced by the stress relief of excavation. Judged from the curves of tangential and deviatoric stress, the surrounding rock in the two sidewalls, the roof and floor are greatly damaged under λ 1.5 respectively. The verification of the numerical simulation experiment is proved by the similar material simulation experiment.