公路隧道充填型岩溶管道突水灾变机理及演化过程数值分析

Mechanism on water inrush disaster of filling karst piping and numerical analysis of evolutionary process in highway tunnel

为研究公路隧道充填型岩溶管道突水灾变机理及其演化过程,针对地质缺陷型岩溶突水构造,建立充填型岩溶管道3种力学失稳模型,对所建立的失稳模型进行力学解析推导,得到相应的失稳判据。以富安省和庆和省之间1号公路的DEO CA隧道发生岩溶突水为典型工程背景,对其突水灾变演化过程展开计算分析,采用真实破裂过程分析程序RFPA和快速拉格朗日Flac3D程序分别对岩溶管道突水灾变的微、宏观演化过程实施数值仿真分析。研究结果表明:岩溶管道充填体的安全系数K=0.46,说明充填体将发生滑移失稳并导致岩溶突水,解析计算结果与现场突水实际相吻合。数值计算结果较好地反映了岩溶管道突水的全过程演化机制。

In order to study the water inrush disaster mechanism and evolutionary process of filling karst piping in highway tunnel, the three types of filling karst pipe mechanical instability model were established aiming at the geological defects for karst water bursting tectonic. The mechanical analysis was deduced and the corresponding criterion was obtained. Taking national highway 1A DEO CA tunnel adjacent to Phu Yen Province and Khanh Hoa Province as the typical engineering background, in which karst water inrush occurred, the water inrush disaster evolution processes were calculated and analyzed. The micro and macro evolution process of the karst conduit water inrush disaster were simulated and analyzed by realistic failure process analysis（RFPA） method and fast Lagrangian method Flac^3 D. The results show that the safety factor of karst pipeline filling body is 0.46, which indicates that the filling body sliding has instability and karst water inrush will occur. The analytical calculation results coincide with the scene actual water inrush. The numerical calculation results can reflect the mechanism and whole evolution process of karst conduit water bursting.