Study on the Influence of Rock Quality Designation on Tunnel Stability
About the author:
1. China Construction Tunnel Co., Ltd., Chongqing 401320, China; 2. School of Civil Engineering, Chongqing University,Chongqing 400045, China; 3. Chongqing Jiangnan Urban Construction and Development（Group） Co., Ltd., Chongqing 400000, China
Abstract:
In order to study the influence of rock quality designation （RQD） on tunnel stability, basedon the Jiangnan Tunnel project, numerical simulation calculation methods were used to analyze thecircumferential stress, kinetic energy and maximum velocity of surrounding rock under different RQDvalues and joint dip angles during rock burst in the tunnel. The research results show that under differentRQD values and joint dip angles, the peak circumferential stress and maximum kinetic energy ofsurrounding rock at an initial geostress of 75MPa are higher than those at an initial geostress of 55MPa.The degree of surrounding rock damage increases with the increase of joint dip angles. The kinetic energyof surrounding rock gradually decreases with the increase of RQD values and increases with the increaseof geostress. When the initial geostress is 55,75MPa, the maximum velocity of the surrounding rock hasextreme values at RQD values of 62,72,82, and a minimum value at RQD value of 92.
