地下洞室地震动态响应规律的影响因素分析

对含节理岩体地下洞室动态响应分析是一个非常复杂的问题,目前研究尚处于探索阶段,基于此应用离散元软件UDEC初步分析了地震荷载作用下,节理倾角、地应力特征以及地震波振幅、频率等因素对含节理岩体地下洞室动态响应的规律。分析结果表明:地震荷载作用下,拱顶位移在节理倾角小于45°时随倾角的增加而增加,大于45°时随倾角的增加而减小,而拱肩均在倾角为60°时位移最大。洞室各验算点位移均随侧压力系数的增加而减小,随地震波振幅的增加而增大。分析结果还表明在低频部分验算点位移随频率的增加而增大,在高频部分随频率的增加而减小。研究思路及结果对含节理岩体地下洞室围岩变形和破坏机制以及抗震工程设计具有指导意义。

Study on Influencing Factors of Dynamic Response of Underground Cavern under Earthquake

The dynamic response analysis of underground cavern with jointed rock is a very complex issue,the current research is still at the exploratory stage. Based on the application of discrete element software UDEC a preliminary analysis was carried out on the dynamic response law of the joint angle, the stress characteristics and the seismic wave amplitude,frequency and other factors to the underground cavern containing jointed rock under seismic loads. The results show that: under the earthquake loads,the arch displacement increases with increasing inclination angle in case of inclination angle less than 45° and decreases when the angle greater than 45°, while the spandrel had the largest displacement at the inclination of 60°. The displacement of checking points in chamber decreases with an increase in lateral pressure coefficient,and increases with the increase of shock wave amplitude. The results also show that in low-frequency part, the displacement of checking point increases with increasing frequency and in the high-frequency section decreases with increasing frequency. These research ideas and results can serve as guide for rock deformation and failure mechanisms of the jointed rock underground cavern,and seismic engineering design as well.