膨胀性软岩隧道致灾机制研究与应用

隧道建设的规模和数量迅速发展，相关理论研究却相对不足，随着隧道越来越多地穿越诸如软弱围岩、溶洞等复杂、恶劣地质区域，对施工技术和理论研究的要求也更高，如何做到规避灾害，安全施工是大家一直关注的问题。以重庆市某公路隧道为依托，对穿越膨胀性软岩段隧道，提出不良地质构造与围岩条件、水的因素、不规则地应力以及工程因素等导致隧道灾害的因素，不同因素相互关联、相互影响，根据分析结果采取相应的防治方案来规避灾害。利用Poyting-Thomoson模型计算隧道围岩变形，与现场监控量测数据相结合，对隧道膨胀性软岩段的围岩变形做出预测，得出最佳二次衬砌支护时间。同时从初支二衬间的应力角度对膨胀性软岩进行了持续监测，表明了膨胀性软岩隧道段防治方案达到了预期目标。从致灾机制来分析隧道建设，可以更好地为工程决策服务。

Research and Application of Induced Accidents Mechanism for Swelling Soft Rock Tunnel

The scale and quantity of the tunnel construction grow quickly. The related theory research is insufficient. With more and more tunnel crossing the complex and poor geological area such as weak rocks and caves, the construction technology and theoretical research are required higher. How to avoid the disasters and safety construction is a concerned issue all the time. Relying on a highway tunnel in Chongqing, the poor geological structure and surrounding rock conditions, water factor, irregular ground stress, engineering factors and factors causing the tunnel disasters are put forward for the tunnel crossing swelling soft rock section. The different factors are all interconnected. According to the results of the analysis, the corresponding prevention scheme is used to avoid the disasters. The Poyting-Thomoson model is used to calculate the deformation of surrounding rock. Combined with the in-site monitoring data, the deformation of the surrounding rock in the swelling soft rock section of tunnel is predicted. And the optimal secondary lining support time is given. At the same time, from the stress angle between the initial support and the secondary lining, the swelling soft rock is continuously monitored, which shows that the prevention scheme for the swelling soft rock tunnel section has reached the expected objective. The tunnel construction is analyzed from the induced accident mechanism, which can better serve for the engineering decision-making.