【摘要】 为准确预测Ⅰ/Ⅱ复合型加载条件下岩石类脆性材料的断裂行为，首先，在传统最大切向应变能密度断裂准则的基础上，考虑裂纹尖端应力场Williams展开式中的非奇异应力项（T应力），建立了考虑T应力的Ⅰ/Ⅱ型裂纹广义最大切向应变能密度断裂准则；其次，探究T应力及泊松比对初始裂纹起始扩展角及起始扩展条件的影响；最后，基于5种岩石材料的中心直裂纹巴西圆盘复合断裂试验结果对该准则的有效性进行验证。研究结果表明：随T应力增大，裂纹起始扩展角逐渐增大，而KII/KIc逐渐减小；随泊松比增大，裂纹起始扩展角及K_Ⅱ/K_Ⅰc同时减小；纯Ⅱ型断裂时，T应力及泊松比对KⅡ/K_Ⅰc的影响最显著；考虑T应力的最大切向应变能密度断裂准则所得结果与室内试验结果相吻合，验证了该准则的有效性。更多还原

【Abstract】 The propose of the study is to accurately predict the fracture behaviors of rocks and rock-like brittle materials under mixed-mode I/II loading conditions. Firstly, based on the traditional maximum tangential strain energy density fracture criterion, a modified mixed-mode fracture model called the generalized maximum tangential strain energy density criterion was proposed by considering the effect of T-stress in addition to the mode I and mode II stress intensity factors in Williams’ series expansion. Secondly, the effects of T-stress and Poisson’s ratio on the fracture initiation angle and the onset of brittle fracture were investigated. Finally, the validity of the modified fracture criterion was demonstrated based on the experimental results of centrally cracked Brazilian disc specimens made of five rock materials. The results show that with the increase of T-stress, the initial crack propagation angle gradually increases, while the KII/KIcgradually decreases. As the Poisson’s ratio increases, both the initial crack propagation angle and KII/KIcdecrease. Moreover, the effects of T-stress and Poisson’s ratio on KII/KIcare more remarkable under pure mode II dominant loading. The generalized maximum tangential strain energy density fracture criterion is in good agreement with the laboratory test results, which verifies the validity of this criterion.更多还原