铁路隧道横洞进主洞关键技术及施工方案优化

Key Technique and Construction Scheme Optimization for The Intersection of the Horizontal Adit and Main Tunnel of Railway Tunnels

以全长922 m某隧道2号横洞为例,首先运用地质调查法、地震反射波法(TSP)、电磁波法(雷达)、超前钻探法等综合超前地质预报技术手段;对横洞进正洞交叉口段围岩情况进行预判与辨识。基于横洞进主洞原设计方案,对交叉口段初期支护受力进行建模和计算;并结合计算结果对支护方案进行了优化;通过对交叉口段围岩收敛变形监测数据分析,证明优化后方案可以满足对施工安全、施工质量以及硐室围岩变形控制的要求,确保了横洞进主洞施工的顺利实施,对类似地质条件下辅助硐室进主洞室的施工技术应用具有重要借鉴意义。

The intersection joint project of some tunnel 2# adit（ length 922 m） to its main tunnel was taken as an example. Firstly,the geological survey method,seismic reflection wave method,electromagnetic waves method and geotechnical advance boring method were used to forecast the geological condition at intersection of the horizontal adit and main tunnel. Secondly,the value of force acted on initial supports of intersection sections was calculated. Based on the calculated results,the original support scheme was optimized. During the construction process,the deformation of surrounding rock was monitored and analyzed. Finally,the optimized support scheme was proved to be effective and the requirement of construction safety,construction quality and surrounding rock deformation were satisfied. The engineering experience obtained could be taken as a significant reference for other similar projects.