Abstract:
The load-structure method has been widely used in the current tunnel design, so it is very important to
determine the rock resistance coefficient reasonably. Taking a deep-buried circular tunnel as the research object,which conforms to the ideal elastic-plastic mode, the stress and displacement of surrounding rock are analyzed base on the Hoek-Brown criterion, which can better reflect the non-linear failure characteristics of rock mass and explain the influence of tensile stress zone and low stress zone on the strength of surrounding rock mass. Then the formula for calculating the rock resistance coefficient is obtained by Winkler hypothesis. Based on the Xiangjiawan tunnel on Zhengzhou-Wanzhou high-speed railway, the engineering application analysis is carried out. The results show that: 1)as for the method of calculating the rock resistance coefficient based on Hoek-Brown criterion, the influences of stress state, structure and strength of rock mass are taken into account, which is more practical; 2) in field application, BQ can be determined by saturated uniaxial compression test, elastic wave velocity test of rock mass and rock, and then GSI can be approximately determined by BQ, finally rock mass parameters can be determined, realizing the quantitative selection of parameters; 3) based on the engineering application in Xiangjiawan tunnel, it is shown that the calculation result of the rock resistance coefficient is close to the recommended range specified in the code, verifying the rationality of the calculation results to some extent.
WANG Zhilong1,
2 ZHOU Renqiang3 YANG Nie1,
2 WANG Mingnian1 etc
.Hoek-Brown Criterion Based Calculation Method of Rock Resistant Coefficient
in Tunnelling and Its Engineering Application[J] MODERN TUNNELLING TECHNOLOGY, 2020,V57(5): 84-90