隧道岩溶突水、突泥危险性评价初探

Preliminary study on risk assessment of water and mud inrush in karst tunnel

通过对渝怀线圆梁山隧道等近20座隧道岩溶突水、突泥机制的深入研究,在充分考虑方法可操作性、适用性,定性与定量评价相结合的基础上,提出了"隧道突水、突泥危险性分级体系"。建立起了以可溶岩的物质结构、地质构造条件、场效应条件、其它条件因素为一级评价指标,以断裂破碎带宽度、承压水压力条件、地形地貌特征、隧道埋深等13个影响因素为二级指标的评价体系。用层次分析法确定了各因素的权重,采用定性、定量相结合的方法确立了各指标的隶属度,并根据隧道突水、突泥危险性级别制定了相应的防治措施。最后以圆梁山隧道毛坝向斜段为例,对隧道突水、突泥危险性进行了分级评价。结果表明,毛坝向斜段隧道突水、突泥极危险区长度为992 m,约占该段总长的54.07%。

Through analysis of more than 20 karst tunnels a risk classification system for water and mud inrush is put forth by means of qualitative and quantitative analysis on the condition that fully considering the operability and applicability of the methods used in the analysis.The 1st-order evaluation index involves the material components of the soluble rocks and geo-tectonic conditions as well as field effect conditions;the 2nd-order evaluation index involves 13 influencing factors such as the width of the faults and pressure of the confined water and the landform as well as the buried depth of the tunnel.In addition,the weights are determined with ATP and the degree of membership by means of qualitative and quantitative method,and the corresponding protect measures is drafted in light of the risk of water or mud inrush in the tunnel.The results show that the very risky part of water or mud inrush in Maoba syncline is 992 m long that accounting for 54.7% of the total tunnel.