小湾水电站坝基岩体质量动态评价研究

摘要

岩体质量随其赋存条件的变化而动态变化,因而坝基岩体质量的动态评价对于大坝工程的安全运营意义重大.本文以小湾水电站坝基岩体的大量测试、监测资料为基础,归纳总结了岩体质量的动态特征,提出了岩体质量劣化、恢复的评价指标,在常规岩体质量分级的基础上引入BQ系统、RMR系统动态评价岩体质量随四维空间的变化特征,建立了Vp-E0关系,并采用Hoek-Brown强度准则,确定各特征点的岩体强度指标.同时,以岩体松弛程度系数为指标,探讨了一种简易的岩体质量预测方法.%As its occurrence conditions changes,the quality of rock mass has corresponding dynamic change.So the dynamic evaluation of rock mass quality for dam foundation is of great significance for the safety of dam operation.This paper is based on a large number of tests and monitoring data of the foundation rock mass at Xiaowan Dam.It summarizes the dynamic characteristics of the quality of rock mass and then puts forward the evaluation index of rock mass quality's degradation and recovery.It also uses the BQ system and RMR system to evaluate dynamically the characteristics of the change of the rock mass quality in the four-dimensional space.Furthermore the relationship between Vp and E0 (Vp-E0) is established and the Hoek-Brown strength criterion is adopted to determine the strength index of the feature points of the rock mass.At the same time,the relaxation degree coefficient of rock mass is used as indicators to examine a kind of simple and easy forecasting method of rock mass quality.