【作者】 陈新； 杨强； 周维垣；

【Author】 Chen Xin;Yan Qiang;Zhou Weiyuan Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China

【机构】 清华大学水利系；

【摘要】 本文引入一个二阶损伤张量Ω来描述节理岩体的各向异性连通情况,法向为n的截面其连通率为ω=n·Ω·n。根据张量代数和热力学要求,采用唯象的方法建立了依赖于损伤的弹性刚度D(Ω)。根据连通率将完整岩体与完全裂隙的内摩擦系数与黏聚力f_r、c_r和f_j、c_j加权平均得到节理岩体的各向异性抗剪材料参数f(n,Ω)和c(n,Ω),从岩体的面抗剪强度准则(莫尔-库仑条件)出发,在主应力空间内导出了具有一阶精度的各向异性强度准则显式表达式F(σ,Ω)=0。根据上述基于二阶损伤张量的节理岩体各向异性模型,研究了各向异性对井壁极限压碎泥浆压力计算结果的影响。更多还原

【Abstract】 A two-order damage tensor Ω is adopted to describe the anisotropic joint connectivity ω of jointedrock masses, so that joint connectivity at any direction can be expressed as ω=n·Ω·n. Damage-dependent elasticitystiffness tensor D(Ω) is formulated by considering tensor algebra and thermodynamic requirements. According tojoint connectivity shear strength parameters of jointed rock masses, friction factor f(n,Ω) and cohesion c(n,Ω)are weighted average of those of entire rock and entire fissures f_r、f_j and c_r、c_j respectively. In principal stressesspace, the explicit anisotropic strength criterion F(σ,Ω)=0 is obtained with one order precision. According to thedamage-dependent anisotropic model for jointed rock masses, the elastic wellbore stability analyses were carried outby FEM, the collapse mud weight affected by rock anisotropic was analyzed.更多还原