破碎岩体流固耦合渗流的分岔

利用承压破碎岩石非Darcy渗流的渗透特性试验规律，对破碎岩体渗流动力系统进行了应力场与渗流场耦合的分岔行为研究.根据多孔介质的有效应力原理建立了含有孔隙度及孔隙压力等渗流物理量的应力场控制方程；考虑流体与固体骨架各自的运动速度，分别建立了流体非Darcy渗流的运动方程以及固体骨架和流体的连续性方程，推导出含有应力场体积应变的渗流场控制方程；得到了垮落破碎岩体由自然堆放状态过渡到压实状态时的弹性流固耦合一维非Darcy渗流的非线性动力学方程组，分析并求解了渗流系统的平衡态，利用逐次亚松弛迭代法分析了平衡态的稳定性，得到了无量纲化孔隙压力、渗流速度随参数变化的动力学响应，指出破碎岩体渗流动力系统存在鞍结分岔.在分岔点处任意微小的扰动易诱发渗流失稳，引发突水等动力学灾害.

Bifurcation of fluid-solid coupling flow in broken rock

Making using of the regularities of seepage properties from the experiments on the non-Darcy flow in confined broken rock,the bifurcation of coupling between the stress field and the flow field were studied on the dynamic system of flow in broken rock.At first,by the principle of the effective stress in porous media,for the stress field the controlling equations involving such flow variables as porosity and pore pressure were established;then taking the kinetic velocity of the fluid and the solid framework into account,the kinetic equation of non-Darcy flow and the continuity equation corresponding to the fluid and the solid were developed respectively,furthermore for the flow field the controlling equation containing the volumetric strain was derived.At last,the nonlinear dynamic equations of one dimensional non-Darcy flow considering the fluid-solid coupling were developed for the caved broken rock changing its state from natural stacking to compaction,and then the steady-states of flow system were analyzed and solved.By the successive lower relaxation iteration,the stability of the steady-states was analyzed and the dynamic responses were obtained for the dimensionless pore pressure and flow velocity varying with the parameter.From the results it is pointed out that there is a saddle-node bifurcation in the flow dynamic system.At the point of bifurcation,an arbitrary tiny disturbance is apt to induce the instability of flow,and result in some dynamic disasters such as water inrush and et al.