针对岩体结构与渗透性对应关系的复杂性,直接建立二者的量化关系模型存在极大的技术难度问题,利用伺服渗透试验结果,分析脆性岩石全应力应变过程中渗透性演化和加载变形破坏特征,得出渗透性变化过程中存在跳跃突变点,该点处的应力和临界破坏强度以及岩石体胀点处应力处于同一应力水平;通过岩石统计强度分析,借助重整化群理论,在岩石试样承载能力概率函数基础上推导出脆性岩石临界破坏强度与峰值应力比值的表达式,该比值随围压增大而减小。用该公式预测伺服渗透试验中的渗透性突变点位置。研究结果表明:大多数脆性岩石预测值与试验值较吻合,误差在0.089-0.058之间,验证了该表达式的合理性。
Based on the fact that it's a great technical problem to establish the quantitative relationship model between rock structure and permeability for the complexity,permeability evolution and load deformation characteristics of brittle rock in complete stress-strain path were analysed based on servo-controlled penetration test.The results show that there is a mutation whose corresponding stress is the same as critical failure strength and the stress of rock volume expansion point in permeability change process.The expression is derived for brittle rock critical failure strength and peak stress ratio which decrease with the increase of the confining pressure through statistical strength and renormalization group theory based on carrying capacity of the rock sample probability function.Permeability catastrophe in servo-control testing is predicted using this formula.Predictive value is in good agreement with experimental value for most brittle rock and the error is from ?0.089 to 0.058.