岩石破裂过程THMD耦合数值模型研究

从岩石的细观非均匀性特点出发,应用损伤力学、热力学和渗流力学理论,建立了岩体热(温度)-水(渗流)-岩(应力)-损伤耦合数值模型(THMD model),把岩石(体)THM耦合问题的研究从应力状态分析深入到损伤、破坏过程分析之中。探讨了THM耦合作用下岩石材料的细观结构损伤及其诱发的材料力学性能演化机制,并运用所提出方法计算温度-渗流-应力耦合作用下井筒近场围岩的稳定性,模拟得到的岩体破坏过程、应力分布、AE特性及渗流特性变化与现场标定结果有着一致的规律性,初步证明了该数值模型的合理性和有效性。THMD模型以简单的数值模型表征了岩石(体)中热、水、岩及损伤之间复杂的作用关系,为从细观损伤演化揭示宏观岩体温度-渗流-应力耦合破坏机制提供了一种新的数值分析方法。

Investigation on coupled thermo-hydro-mechanical-damage(THMD) model for rock failure process

Based on the heterogeneous characteristics of rock at mesoscopic level,the thermo-hydro-mechanical(THM) coupled action during the failure process of rock subjected to THM loading is described with elastic damage mechanics,thermal-elastic theory and seepage mechanics.A mesoscopic thermo-hydro-mechanical-damage(THMD Model) coupling model,implemented in RFPA,is proposed.In the numerical model,the damage and associated mechanical properties evolution of mesoscopic structure in rocks subjected to THM loading was discussed.Numerical simulation is carried out to investigate the stability of near-field rock mass around a vertical borehole subjected to coupled thermo-hydro-mechanical loading.The numerically obtained stress field,failure pattern,associated AE events and permeability evolution are all agree well with the in-situ data,which prove that the proposed model is reasonable and effective.The proposed technique is significantly meaningful for the investigation of failure mechanism of rock subjected to coupled thermo-hydrologic-mechanical loading.