广西谢家峒隧道大溶洞溶腔稳定性分析

The Large Karst Cave Cavity Stability Analysis in Guangxi Xiejiadong Tunnel

在岩溶地区修建隧道工程经常遇到溶洞坍塌事故的发生,广西谢家峒隧道大溶洞6m厚顶板突然整体坍塌,经过国内知名专家多次勘察、判断、分析,得出溶腔壁围岩的稳定性无法确定的结论。采用有限元分析了溶洞溶腔的应力应变变化规律和溶腔的稳定性,结果表明,谢家峒溶洞在天然状态下仍处于不稳定状态,溶腔壁两侧和洞顶所受压应力较大,所受的应力已超出了围岩的承载力范围,洞顶的岩石仍有坍塌的风险,腔壁存在局部岩爆的风险。

The occurrence of Karst collapse is often in Karst region when construction of tunnel engineering in Karst region. Guangxi Xiejiadong tunnel Karst cave collapsed as a whole suddenly. After a domestic famous expert survey,judgment,and analysis for many times,they concluded that dissolved cavity wall surrounding rock stability of uncertain conclusion. In this paper,the finite element analysis of Karst cave dissolved cavity stress and strain change rule and the stability of rock-salt cavity,Analysis results show as follows: cave in natural state is still in a state of flux,on both sides of the cavity wall and ceiling the compressive stress is larger,all the stress is beyond the scope of the bearing capacity of the surrounding rock,roof rock still has the risk of collapse,the cavity wall exists local risk of rock burst.