【摘要】 用类岩石材料白水泥多裂纹模型进行了双向加压实验。实验结果表明 ,在各种侧压σ2 下 ,宏观强度σc1基本上随α增加而变大 ,但在α=4 5 左右呈现最低值 ;随着侧压σ2 增加 ,宏观强度σc1明显提高。用εθmax及σθmax断裂判据对单个裂纹进行了分析 ,所给出的初始开裂角理论值与该多裂纹模型实验值非常相符 ,对初始开裂载荷 ,能给出多裂纹模型实验值的上限。以单向加压实验结果为基础 ,建立了便于工程应用且适用于多裂纹体的等效正交各向异性本构关系。由此本构关系所得的计算结果与双向加压实验结果符合良好。更多还原

【Abstract】 A series of biaxial compression experiments, dealing with the effects of regular cracks in replicated rock mass, have been carried out. The results show that the macro strength σ c1 increases basically with the increasing inclined angle α of crack and remarkably with the increase ing side compression σ 2 . But when α ≈45?, σ c1 becomes the lowest. The initiation angle θ of the cracks and the up limit of the critical fracture load can be estimated well by the mixed mode fracture criterions of ε θ max and σ θ max . Based on the results of uniaxial compression experiments, an orthotropic constitutive relationship is constructed, which can be applicable to the multi cracked body problem of mining and other underground engineering. The computed results by this relationship agree well with the biaxial compression experiment results.更多还原