Hoek-Brown准则在深埋隧洞围岩稳定性分析中的应用

Application of Hoek-Brown Failure Criterion to Stability Analysis of Surrounding Rocks of Deep-Buried Tunnels

岩体工程中通常采用的Mohr-Coulomb准则不能动态反映岩体破坏时的力学行为,因而对于深埋地下工程的分析计算与实际存在一定的偏差,而非线性的Hoek-Brown准则能弥补其不足.通过对比分析Mohr-Coulomb准则和Hoek-Brown准则,用Hoek-Brown准则推导得出的瞬时内聚力和瞬时内摩擦角来代替Mohr-Coulomb准则中的相应参数,结合具体工程实际运用FLAC3D进行深埋隧洞开挖的数值模拟,并与直接运用Mohr-Coulomb准则计算进行比较.结果表明:基于Hoek-Brown强度准则的结果在竖向位移和塑性区都稍大于基于Mohr-Coulomb准则计算得到的结果,其更加符合工程实际.

The Mohr-Coulomb failure criterion used in rock engineering cannot reflect the mechanical behaviors dynamically during the failure process,which cause certain deviation for analysis and calculation of deep underground projects compared with the actual situation.However,the nonlinear Hoek-Brown failure criterion is able to make up for the shortcoming.The instantaneous cohesion and the instantaneous internal friction,deduced by Hoek-Brown failure criterion,replaced the corresponding parameters in the Mohr-Coulomb failure criterion by comparing and analyzing the Mohr-Coulomb failure criterion and the Hoek-Brown failure criterion.Combining with practical project and using FLAC^3D,the numerical simulations are made by this method;and then comparing the results of applying the Mohr-Coulomb failure criterion directly.The results show that the application of Hoek-Brown failure criterion to calculate and analyze underground engineering is feasible and more in line with practical projects.