地下工程破坏机理认知对工程建设风险的影响

随着岩土力学与地下工程施工技术的发展,尤其是近年有限元极限分析法引入到地下工程稳定分析中,隧洞的破坏机理日益清晰。该文研究了地下工程的破坏机理,采用模型试验和有限元分析法模拟,提出了深埋隧洞围岩破坏与围岩压力主要来自隧洞两侧的观点,以及随埋深而变的隧洞破坏机理,分析了普氏压力拱存在的问题。该文指出当前隧洞建设中事故高于其它土木工程的原因,主要是由于地下工程客观地质环境复杂,以及人们对破坏机理认知不足,对客观条件的掌控能力有限。同时,该文还对隧洞建设中的各种坍塌事故与风险进行了分析,通过实例阐明了隧洞破坏机理认知对隧洞建设风险的影响。

Impact of Recognition of Underground Engineering Failure Mechanism on Engineering-Construction ]gisks

With the development of geotechnical mechanics and construction technology of underground engineering, especially with finite element limit analysis introduced into stability analysis of underground engineering in recent years, the tunnel failure mechanism becomes distinct gradually. The failure mechanism of underground engineering is studied by doing model test and simulation of finite element limit analysis. The point that the failure and pres- sure of the surrounding rock of deep underground tunnel are mainly fi＇om the two sides of tunnel along with failure mechanism for the change of buried depth is presented. The existing problems of Platts pressure arch are also analyzed. The causes bringing about more accidents in tunnel construction than in other civil engineering are pointed out： complicated geotechnical environment, insufficient recognition of failure mechanism and limited control ability over objective conditions. Various kinds of failure accidents and risks in tunnel construction are analyzed and the impact of recognition of tunnel failure mechanism on risks in tunnel construction is also illustrated.