层状裂隙岩体蠕变柔量估计的合理方法

基于Taylor模型方法和粘弹性断裂力学理论，推导了层状裂隙岩体的单轴、剪切以及体积蠕变柔量，并合理考虑了裂隙相互作用效应的影响，分析了层状裂隙岩体单轴蠕变和剪切蠕变的各向异性。计算分析指出，裂隙岩体的单轴蠕变柔量随裂隙密度参数的增加而增大，随裂隙倾角的增加而减小。考虑裂隙相互作用效应时，层状裂隙岩体的蠕变柔量明显大于不考虑裂隙相互作用的情况。该方法为通过室内岩石流变实验了解实际工程中裂隙岩体的蠕变特性提供了一种可能。

REASONABLE METHOD TO ESTIMATE CREEP COMPLIANCE OF ROCKS JOINTED BY PARALLEL CRACKS

Based on Taylor model and viscoelastic fracture mechanics,a method is proposed to estimate the uniaxial,shear and voluminal creep compliance of rocks jointed by parallel cracks. First,the interaction of parallel cracks is neglected and the anisotropic creep compliance of Taylor media is computed. Then each single crack is placed in Taylor media to account for the influence of other cracks on its creep behavior. Based on the above analysis,the creep compliance of rocks jointed by parallel cracks is derived. The effect of interaction among cracks is taken into account and the creep anisotropy of cracked rocks is analyzed. According to the analysis results,uniaxial and shear creep compliance of cracked rocks increases with increment of crack density parameter and decreases with increment of crack dip. The creep compliance with account of interaction among cracks is obviously bigger than that without of interaction among cracks. The proposed method makes it possible to estimate creep compliance of cracked rocks only by experimental study on rock samples in laboratory.