黄土公路隧道浅埋段管棚注浆支护机理及监测分析

Support Mechanism and Monitoring Analysis of Pipe Roof Grouting for Loess Highway Tunnel in Shallow-buried Section

为了探讨管棚注浆法在黄土公路隧道浅埋段中的支护机理和实际应用效果,对某黄土公路隧道右线出口段进行了地表沉降、拱顶下沉和水平收敛等的施工监测;在对现场监测数据进行分析的基础上,得出黄土公路隧道洞口浅埋段在管棚支护作用下拱顶下沉、水平收敛、地表沉降等的变化规律。研究结果表明:管棚注浆法能够显著抑制浅埋黄土地层的变形和拱顶下沉,减少隧道初始支护结构的变形和受力,避免浅埋黄土地层开挖中塌方现象的产生,保证了施工安全,为进一步分析黄土地区管棚注浆法的支护机理提供了参考依据,同时也为今后西北地区黄土公路隧道管棚注浆法的设计和施工提供了优化数据。

To discuss the support mechanism and practical application effect of pipe roof grouting mehtod for loess highway tunnel in shallow-buried section,the dynamics measures,such as ground settlement,vault crown settlement and level convergence were made in outlet section of right line of one loess highway tunnel.Based on studying the field monitoring data,the change regulations of shallow-buried section of loess highway tunnel entrance,such as vault crown settlement,level convergence and ground settlement were obtained.Research results show that the method of pipe roof grouting can clearly restrain the deformation and vault crown settlement for shallow-buried layer of loess,and reduce the deformation and stress of tunnel initial support structure,avoid caving in excavating of shallow-buried layer of loess and provide the security reference for the construction work.It provides the reference basis for further analysis of the support mechanism of pipe roof grouting method in loess area,meanwhile,it provides optimized data for the design and construction of pipe roof grouting method for loess highway tunnel in the loess region of North-western China in the future.