复杂地质条件下初始地应力场模拟的数值流形方法研究

Study on Numerical Manifold Method of Simulation for in Situ Under Complex Geological Conditions

数值流形方法分析岩土工程问题使用初应力模块施加初应力,但初应力在分析初始阶段易发生消散,无法有效保持.针对深埋问题本文提出在模型边界施加面力的方法来保持初应力.通过对均质各向同性、均质各向异性、非均质材料体进行验证,证明了所提方法的可靠性,随后将其运用于含裂隙复杂地质条件下初始地应力的模拟,并于UDEC计算结果进行对比.分析结果表明,该方法对数值流形方法的初始应力保持中具有积极效果,为采用数值流形方法开展数值模拟提供了有效支撑.

In the original NMM code developed by SHI,we use an option to specify the level of initial stresseswhich are applied everywhere in the modeled domain from the beginning of the analysis.However,the initial stressesdissipate rapidly at the start of the analysis,and they cannot be maintained at their original level.For deep undergroundproblems we advise to impose in situ stresses by applying tractions on the boundaries.Then through the simulationon the problems of isotropic homogeneity,anisotropic homogeneity and heterogeneity respectively,we can prove theaccuracy of this method.After that,we use it to simulate the problem of complex geological condition which containsfractures,and find it worked well compared to the result of UDEC.In conclusion,this method has position efforts onmaintaining initial stresses in NMM.