基于地质概化的坚硬厚基岩覆岩裂隙场演变特征研究OA北大核心CSTPCD

Accurately grasping the evolution characteristics of the water-conducting fracture zone in the mining overburden is an im-portant basis for preventing the occurrence of water inrush disasters in the working face,especially for the high strength mining con-ditions in the western mines.Taking the 201 west wing area of Yushuwan Coal Mine as the background,taking the uniaxial com-pressive strength of each sandstone layer,RQD,and thickness of sandstone layer as the system cluster analysis indexes,this paper proposes a geological generalization method for thick bedrock,systematically studies the influence of different bedrock layer thick-ness on the development height,fracture angle,frequency,and joint strain energy evolution law of the water-conducting fracture zone,and determines the quantitative relationship between the height of the water-conducting fracture zone and the total joint strain energy.The research results show that:the development height of the hydraulic fracture zone simulated based on the geological gen-eralization method presents a log-positive correlation increasing trend with the increase of the bedrock thickness,and the increasing rate gradually decreases.This law is verified by comparing with the measured results of the adjacent mines;with the increase of the thickness of bedrock,the development frequency of vertical cracks in the water-conducting fracture zone increases significantly,while the horizontal cracks in the water-conducting fracture zone increase,which indicates that the increase of the thickness of bed-rock has a certain inhibition effect on the initiation and expansion of horizontal cracks in the water-conducting fracture zone;the de-velopment height of the water-conducting fracture zone is closely related to the energy release degree of the overlying rock.It in-creases exponentially with the increase of the maximum strain energy and the total strain energy of the joint,and the increasing rate gradually increases.