Research On The Fractured Rock Crack Propagation Based Seepage-stress Coupling

Mining engineering study contains a large fractured rock, Which is rich in a largenumber of cracks it with other homogeneous media have different mechanicalproperties，Mainly affected by mining groundwater flow in fractured rock and rockstress joint action.So Research the law of cracks initiation, propagation in fracturedrock under coupling seepage and stress state has important significance.In this paper,Comprehensive application of theoretical analysis and numerical simulation methodsand other methods based on the perspective of water pressure and lateral pressure acton fractured rock and crack propagation in fractured rock., Systematic study the lawof crack propagation of the fractured rock under stress and seepage coupling. Themain research results are as follows.(1) Based on the theory of fracture mechanics and classical mechanics, Derivedformulation of fractured rock crack propagation length under seepage and stresscoupling; Use of maximum circumferential stress theory, derived single crackinitiation criterion in the stress state of tension, pure shear, tensile shear stress andpressure shear stress; And the derivation Crack propagation strength of two collinearcracks, and the two nonoverlap cracks and two overlap cracks under seepage andstress coupling.(2) Using Extended finite element established fractured rock samples model.Numerical calculation of the fractured rock in a single cracks and two crackspropagation process under seepage and stress coupling. Analysis of the effects oflateral pressure and water pressure on a single crack propagation, And two cracks atdifferent water pressure variation of crack propagation.(3) Analysis of water blocking capability of impermeable layer under theinfluence of two factors of impermeable layer thickness and length of the workingface; Derivation the formulation of rock bottom water bursting pressure limit, Andestablish the corresponding numerical model, Simulate floor crack propagationprocess under different length of working face and impermeable layer thickness,Analysis of the basic laws of impermeable layer of water-blocking ability.