地表高压旋喷桩加固技术在新屋隧道浅埋段的应用研究

Application of Surface High Pressure Jet Grouting Pile Reinforcement Technique in Shallow-Buried Section of Xinwu Tunnel

为解决隧道浅埋段覆盖层遇水软化、开挖时易发生坍塌、出现涌突水等地质灾害难题,常采用高压旋喷桩地表加固技术进行加固,现场施工多以经验为主,加固效果难以保证。总结了地表高压旋喷桩加固技术的施工工艺,分析了其常见技术难题,提出了解决措施,并在依托工程新屋隧道洞身浅埋段应用;加固完成后,通过强度试验、现场监测、现场钻孔检查等手段对其加固效果进行了定性分析及评价。结果表明,加固区强度、稳定性、抗渗性均有较大提升,加固效果良好。

In order to solve the geological hazard problem that the overburden of shallow buried section of tunnel softens in water,and is easy to collapse and cause water inrush during excavation,the surface reinforcement technology of high-pressure jet grouting pile is often used for reinforcement.The site construction is mainly based on experience,and the reinforcement effect is difficult to guarantee.This paper summarizes the construction technology of surface high-pressure jet grouting pile reinforcement technology,analyzes its common technical problems and puts forward the solutions,which are applied in the shallow buried section of Xinwu tunnel.After reinforcement,the reinforcement effect is qualitatively analyzed and evaluated by means of strength test,on-site monitoring and on-site excavation inspection.The results show that the strength,stability and impermeability of the reinforcement area are greatly improved,and the reinforcement effect is good.