某跨海隧道地质选线及勘察控制要点分析

Analysis of Geological Route Selection and Survey Control Points of a Subsea Tunnel

隧道选址阶段的地质比选是综合选线的重要组成部分。某铁路工程跨海段拟采用海底隧道,隧道地处花岗岩建造基底,风化深槽和球状风化发育。地质比选主要包括跨海平面位置比选、隧道埋深比选、隧道单双洞比选、施工方法(盾构发、矿山法)比选。以海底隧道方案进行地质控制因素分析,梳理了平面及纵断面选线、施工工法、综合勘察方法及手段、岩土参数等控制要点,最终推荐该海底隧道浅埋走行于全风化及碎块状强风化地层。研究成果以期为类似工程提供参考。

Geological comparison in the tunnel site selection phase is an important part of comprehensive route selection.Taking the subsea section of railway project as an example,it was planned to construct a subsea tunnel in a granite bedrock area with deep weathered grooves and spheroidal weathering development.The geological comparison and selection mainly included the comparison the subsea plane position,tunnel depth,single or double-tube tunnel,and construction methods(shield method,mining method).This paper analyzed the geologically controlling factors based on the subsea tunnel scheme and provided an analysis of key controlling points such as horizontal and longitudinal alignment selection,construction methods,comprehensive survey methods and techniques,and geotechnical parameters.The final recommendation is that the subsea tunnel be shallowly buried in fully weathered and fragmented weathered formations.The conclusions are expected to provide a reference for similar projects.