数值方法所得出结论的可靠性很大程度上取决于岩体力学参数的选取，因此基于损伤演化分析，对损伤变量与围岩力学参数之间关系进行了研究。在各向同性损伤的假定下，通过分析开挖过程中围岩损伤演化，建立了采用损伤变量对弹性模量、泊松比、黏聚力、摩擦角等围岩材料参数进行估算的方法。采用弹性纵波波速定义初始损伤，根据壁城隧道现场监测资料建立ANSYS渐进性数值模型，反演典型断面开挖过程中围岩的宏观力学参数。分析结果表明，该方法可以有效地确定围岩力学参数的变化情况，与实际情况吻合较好。

The reliability of the conclusion by numerical methods depends on the selection of mechanical parameters of rock mass. Based on the damage evolution analysis of rock, the relationship between the damage variable and the mechanical parameters is studied. It brings forward a method of estimating rock material parameters (elastic modulus, Poisson’s ratio, cohesion and friction angle) by damage variable. Firstly, it analyzes rock damage evolution process of highway tunnel in excavation by bifurcation orientation. Secondly, it defines the initial damage variable by elastic p-wave velocity, and sets up ANSYS numerical model of the progressive destruction tunnel according to the site monitoring data of Bicheng tunnel. An example is given to estimate and analyze the macroscopical mechanical parameters of various surrounding rocks. The analytical results reveal that this method can effectively determine the magnitude and estimate the macroscopical mechanical parameters.

交通部西部交通建设科技项目（No.200631874024）。