矿井突水过程中承压水水力劈裂机制及渗流稳定理论

In situ tests were used to research the variations of the permeability of floor rocks and movements of rocks in the process of mining. Note that the variations of influence of mining in different slicing on the floor rocks were investigated. The double torsion specimens were utilized to analyze the growth of cracks subjected to the loads of confined water and to present the parameters of fracture mechanics. And the mechanisms of crack growth under the confined water was analyzed. These testing results are important for establishing seepage stability of floor rocks in the process of mining. Moreover, the mesoscopic model of rocks are developed based on the failure mechanisms of rocks. In establishing the mesoscopic model, the deformations of rocks are divided into three parts, i.e. the deformation of rock matrix, the deformation induced by the closure and sliding of cracks and the interaction between cracks, and the deformation induced by the crack growth. The corresponding formulea of calculating the displacements were given, repsectively. Thus, the deformations are added together to form the total deformation of the rock in the process of loading. The mesoscopic model can be used to study the mechanisms of rock failure. In numerical methods, we developed the generalized Kelvin solution based boundary element method (BEM) and the BEM can further be used to analyze deformation and stress distribution of rock stratra in mining. The BEM has obvious advantages over other numerical methods in efficiency and accuracy. Based on the in situ seepage test and double specimen experiments of confined-water induced crack growth, a coupled model of permeability coefficients and confined-water induced crack growth was developed and the computer codes of the model were written in the existing computer codes of three-dimensional nonlinear finite element method.The proposed methods have been employed to analyze the stabiltity of the floor rocks in working faces threaten by the confined water. The results show that the methods have satifactory accuracy and calculational speed. The above-mentioned results are being used for the analysis of the stability of floor rock stratra in the coal production threaten by the confined water. It is believed that the theory of preventing water irruption will be widely used in coal production.

本课题针对矿井在采掘过程中承压水的再度导升现象，采用理论和试验相结合的方法，研究矿井突水过程中承压水的水力劈裂机制。在此基础上，研究渗流对结构面的软化作用，将裂隙的渗流与承压水的水力劈裂相耦合，建立裂隙岩体的渗流基本方程。并应用损伤力学和突变理论，建立裂隙岩体的渗流稳定理论。该理论可望为矿井防治水提供一种新的方法。.....