地下水封洞库通常在花岗岩等硬质岩体中开挖形成,其库区地质构造多发育有断裂构造、节理裂隙等不良地质结构。为了探究断层破碎带对地下水封洞库洞室稳定性的影响,依据湛江地下水封洞库库址区地质构造及地应力实测资料,基于FLAC^3D有限差分软件,分析了断层破碎带距洞室不同距离时的围岩位移及模型断面典型位置的位移。结果表明:①断层破碎带位置对洞室近边墙围岩稳定性影响较大,对远边墙围岩稳定性影响较小;②当断层破碎带距离近边墙的距离超过1/2洞室跨度时,断层破碎带对洞室围岩稳定性影响可忽略。研究成果对于类似洞库工程选址及安全距离的选择具有良好的指导作用。

Underground water-sealed caverns are usually excavated in granite and other hard rock masses where defective geological structures such as faults and joints develop well. In an attempt to investigate into the influence of fault fracture zone on the stability of underground cavern, we examined the displacements of surrounding rock and typical sections in FLAC^3D with varying distance between fault fracture zone and cavern. The conclusions are as follows: (1) The location of fault fracture zone has great influence on the stability of surrounding rock of adjacent side wall, but has little influence on the stability of surrounding rock of distant side wall; (2) When the distance between fault fracture zone and cavern exceeds half of the cavern span, the influence of fault fracture zone on the stability of surrounding rock can be neglected. The conclusions are of guiding importance for determining the safe distance and selecting the location of such caverns.