摘要
针对地下工程稳定性分析与优化的常规指标在高地应力条件下的局限性及传统的能量释放率岩爆指标把岩体看成不发生脆性破坏线弹性体的不足,提出局部能量释放率新指标。该指标的实现是通过在数值计算中追踪每个单元弹性能量密度变化的全过程,记录单元发生脆性破坏前后的弹性能密度差值,得到单位体积岩体突然释放的弹性能量。该指标可更好地定量预测高地应力下地下工程开挖过程中岩爆发生的强度、破坏位置与范围,由该指标求出的围岩释放能又可作为地下工程开挖方案的优化指标。对太平驿水电站引水隧洞工程不同开挖步长下能量释放率指标的算例进行分析。分析结果表明,该指标具有一定的科学合理性。最后将该指标应用于黄河拉西瓦水电站大型地下厂房的开挖方案优化,用于指导该工程的科学设计与施工。
In response to the limitation of conventional index for stability and optimal design of underground rockmass engineering with high geostress and the drawbacks of conventional energy release rate（ERR） rockburst index based on linear elastic theory without brittle failure phenomenon, local energy release rate（LERR）, a new rockburst index is proposed. LERR is obtained through tracing the variety of elastic energy density of each element and recording the maximal fluctuation when brittle failure happens during numerical calculation. With the new index, the intension of rockburst and the position and extent of failure zone can be predicted quantitatively during rockmass excavation under high geostress. Furthermore, total energy release of surrounding rockmass obtained by LERR can be used as optimal index for optimal design of excavation schemes. The results of example analysis of diversion tunnel of Taipingyi Hydropower station show that LERR is rational. Finally, LERR index is applied to optimal excavation scheme of the large underground powerhouses engineering of Laxiwa Hydropower Station at Yellow River.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2006年第12期2453-2460,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家重点基础研究发展规划(973)项目(2002CB412708)
国家杰出青年科学基金资助项目(50325414)
关键词
岩石力学
稳定性分析
高地应力
岩爆
能量释放率
局部能量释放率
弹性释放能
rock mechanics； stability analysis； high geostress； rockburst
energy release rate； local energy release rate
elastic release energy
