滇中引水工程凤凰山隧洞过活动断裂带结构适应性研究

滇中引水工程输水建筑物多采用隧洞,占比高达92%,线路多次穿越区域性活动断裂带等地质条件复杂的地层,工程建设及安全运行均受到严重威胁。结合滇中引水工程隧洞穿越活动断裂带的工程设计案例,从建筑物结构型式选择以及结构对断裂带蠕滑变形及黏滑变形的适应性进行了三维仿真分析,并提出了工程运行期合理的检修年限。研究结果表明:采用短衬砌和宽变形缝结构形式可有效减小区域性活动断裂带位移产生的结构应力,大大延长了衬砌结构的使用寿命。研究结论为穿越活断裂隧洞的抗错断设计提供参考。

Structural Adaptability of Fenghuangshan Tunnel of Central Yunnan Water Diversion Project to Active Fault Zone

Tunnels account for 92% of the water conveyance structures in Central Yunnan Water Diversion Project. The tunnel line confronts with regional active fault zone and strata with complex geological conditions for multiple times, posing threats to the construction and safe operation of the project. The engineering design case of a tunnel of the Central Yunnan Water Diversion Project crossing active fault zone is taken as research background. The structural type of the tunnel is selected, and the adaptability of tunnel structure to creep deformation and stick-slip deformation of fault zone is investigated via three-dimensional simulation, and the reasonable age of service before overhaul in the operation period of the project is put forward. Results manifest that short lining and wide deformation joint can effectively reduce the structural stress caused by the displacement of regional active fault zone, and prolong the service life of the lining structure. The research findings offer reference for the anti-fault design of tunnels.