以岩体中受单向轴力压缩的中心斜裂纹为研究对象,基于修正的最大周向应力判据 MTS 分析了裂隙岩体破坏过程中Ⅰ-Ⅱ型复合裂纹的扩展规律及断裂特性。修正的断裂判据考虑了裂纹间的摩擦系数、闭合度和平行于主裂纹尖端的非奇异项 T 应力,并分析了这些参数对主裂纹尖端应力强度因子及裂纹开裂角的影响。结果表明:裂纹的断裂角不仅与主裂纹特征和载荷方向有关,还与载荷大小间接相关;岩体裂纹间的摩擦系数和闭合度只对 K Ⅱ有负向影响;T 应力的存在及大小对周向应力的最大值及其位置有较大的影响。
Regarding the central incline crack in the rock mass under aniaxial compression as the study object ,the Ⅰ -Ⅱ mixed crack mode and fracture properties of fractured rock mass were analyzed based on the modified MTS(maximum tensile stress) criterion .The crack friction coefficient ,crack closure degree and the T-stress which is a non-singular stress term and parallel to main crack tip were considered in the modified MTS criterion ,and the effects of these parame-ters on stress intensity factors and propagation angle were analyzed .The results suggest that the propagation angle of main crack is not only related to the characteristics of main crack and load direction ,but also ralated to the load size indirect-ly .The friction coefficient and crack closure degree only have the negative impact on K Ⅱ .The existence and size of T-stress have the larger effect on the maximum value and location of tensile stress .