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用FDEM-flow方法作为工具,研究材料的均质度、空间排列对水力压裂的影响。研究表明,随着注入水压的增大,圆孔周界的最大主应力增大,增大到一定值,产生裂隙,裂隙主要由受拉破坏产生。裂隙穿过的区域出现拉应力释放,裂隙端部的应力集中区随裂隙的扩展而向外移动。均质度系数较小时,分叉裂隙较多,裂隙扩展路径不平整,并呈现出非对称性;均质度系数增大,分叉裂隙减少,裂隙扩展路径越平直,呈现的对称性越明显。起裂压力也随均质度系数的增大而增大并趋于稳定。材料的空间排列不同,其起裂位置、扩展形态均有较大的差别,起裂压力也随之波动。
The FDEM-flow method was used as a tool to study the effect of material homogeneity and spatial arrangement on hydraulic fracturing. The results show that with the increase of injection pressure, the maximum principal stress in the perimeter of the circular hole increases and increases to a certain value, resulting in cracks, which are mainly caused by tension failure. Tensile stress is released in the region where the crack passes, and the stress concentration zone at the tip of the crack moves outward as the crack expands. When the coefficient of homogeneity is small, the number of bifurcated cracks is larger and the path of crack propagation is not smooth and shows asymmetry. The coefficient of homogeneity increases, the number of bifurcated cracks decreases and the crack propagation path becomes more straight. The symmetry obvious. The cracking pressure also increases with the increase of the homogeneity coefficient and tends to be stable. The spatial arrangement of materials is different, the initiation position and the expanded shape of the materials have great differences, and the cracking pressure also fluctuates.