小湾水电站地下厂房洞室群弹脆塑性分析

针对小湾水电站枢纽区岩性特点与所处的地应力环境,采用脆塑性本构模型,分析了地下厂房洞室群开挖后围岩的变形与破损区;同时比较了使用脆塑性与弹塑性本构模型时计算结果的差异。由于地下厂房洞室群区域受到多条断层切割,洞室开挖完成后,在断层经过的部位,断层对洞室的变形与破损区有一定的控制作用。针对工程中所关心的断层对洞室稳定性的影响程度,通过断层材料的置换,定量地给出了在断层经过的区域、断层对洞室表面的变形的影响以及断层对洞室围岩的破损区的影响。

ANALYSIS OF UNDERGROUND POWERHOUSES IN XIAOWAN HYDROPOWER STATION BY ELASTIC-BRITTLE-PLASTIC CONSTITUTIVE MODELS

In response to the characteristic of rock masses and initial geostresses in Xiaowan Hydropower Station,elastic-brittle-plastic(EBP) constitutive model is employed to analyze the deformation and plastic zone of the rock mass surrounding the underground structures after the completion of excavation.Meanwhile,elastic-plastic(EP) model is also applied to analyse the problems.The results obtained by the two models are compared and the difference between them is obvious.Considering that several faults intersect the underground caverns,the effects of the faults on both deformation and the damage zone by the replacement of the infillings of them are presented.Numerical results show that faults exert much influence on the stabilities of the caverns when the faults are near the surfaces of the caverns.