煤矿安全2026，Vol.57Issue(1)：1-10,10.DOI:10.13347/j.cnki.mkaq.20241044
深煤层弱固结面与水力裂缝相交扩展规律研究
Study on the interaction and propagation patterns of weakly consolidated interfaces and hydraulic fractures in deep coal seams
摘要
Abstract
Coal seam reservoirs contain a large number of weakly consolidated interfaces such as cleats,bedding,and natural frac-tures,which,along with complex pore structures,make the prediction of fracture propagation patterns during hydraulic fracturing challenging.Understanding the intersection and expansion rules of hydraulic fractures with coal seam weakly consolidated interfaces can facilitate comprehensive and effective permeability enhancement in coal seams through fracturing.We establish a model for the expansion of hydraulic fractures on weakly consolidated interfaces based on the cohesive element method,considering the occur-rence of weakly consolidated interfaces and their distance from the perforations,analyze the impact of different approach angles and strengths of weakly consolidated interfaces on the intersection and expansion patterns of hydraulic fractures at different length to dis-tance ratios(the ratio of the weakly consolidated interface length(L)to the distance(D)from the injection point to the center of the interface).The results indicate that when the length to distance ratio(L/D)is 1/3,2/3,1/1,as the approach angle increases,so does the fracture deflection angle;when L/D is 1/3 or 2/3,the total fracture length gradually decreases with increasing approach angle;when the aspect ratio is 1/1,the total fracture length gradually increases with the increase of the approach angle;when the approach angle is≤15°,hydraulic fractures are more likely to extend along the direction of the weakly consolidated interfaces after intersec-tion,whereas when the approach angle is≥30°,hydraulic fractures tend to penetrate the weakly consolidated interfaces;the fracture width is maximum when the approach angle is 30°;as the strength of the weakly consolidated interfaces increases,both the fracture deflection angle and the modified fracture length show an increasing trend.关键词
煤层压裂/黏聚力单元/裂缝相交/弱固结面/长距比Key words
coal seam fracturing/cohesive element/fracture intersection/weakly consolidated interfaces/length-to-distance ratio分类
矿业与冶金引用本文复制引用
徐敏,孔祥伟,陈青,谢昕,张少斌,谢广宇,徐洲..深煤层弱固结面与水力裂缝相交扩展规律研究[J].煤矿安全,2026,57(1):1-10,10.基金项目
中海油"十四五"规划重大资助项目(CCL2022RCPS0471RSN,CCL2022RCPS0038ESN) （CCL2022RCPS0471RSN,CCL2022RCPS0038ESN）
