在以往室内压密试验的基础上,利用变量依存性本构方程对压密试验中试样的压密特性进行数值模拟.本构方程中,假定岩石破坏速度随着破坏接近度SV的增加而增大;将破坏接近度扩展到三维应力状态,且在破坏接近度为负值的区域,引进强度恢复参数Hp,(Hp=-Sv);通过假定压密岩石强度的恢复程度依赖于恢复参数Hp,,对本构方程进行修正.从数值模拟结果可以看出:在压密过程中依存性变量λ逐渐变小时,修正后的本构方程可以描述压密过程中岩石的性质;尽管还需进一步研究和完善修正本构方程,但其具有较强的应用前景,能够较好地描述压密试验中破碎岩石的压密特性,解释地下建筑物围岩开挖扰动区的恢复现象.%The variable-compliance-type constitutive equation is employed in this study. The constitutive equation can express the failure process of rock, which has been well proved heretofore. In the constitutive equation, it is assumed that the rock fails at a rate which depends on stress severity. The concept of stress severity Sv is expanded to the stress state where Sv take negative value and the healing parameter Hp= -Sv is introduced. The constitutive equation is also modified assuming that fractured rock is gradually compacted or healed at a rate which depends on the healing parameter. According to the results in this study, it can be said as follows. (1) The equation expresses the behaviors of the fractured rock when the compliance becomes smaller in the compaction test. (2) Though further discussions are essential in the future definitely, it can be said that the modified variable-compliance-type constitutive equation shows much potential for simulating the behaviors of fractured rock in compaction test and interpreting strength recovery of rock in loosening zone or excavation damaged zone around an underground structure.
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