隧道围岩动态变形规律及控制技术研究

基于前人既有研究成果和日本龟浦隧道围岩变形试验,结合郑西客运专线大断面黄土隧道围岩大变形的工程实践,阐述隧道施工影响下围岩变形动态规律,提出围岩变形控制的技术要点和技术措施,并提出相应的围岩变形控制建议.研究结果表明：隧道开挖后的围岩变形可分为掌子面前方的先行变形、掌子面变形及掌子面后方变形3种形式,且这3种变形是同时发生的.控制开挖工作面失稳、拱顶失稳、拱脚下沉和围岩大变形等是隧道围岩变形控制的要点.开挖过程控制和辅助工法控制是隧道围岩变形控制的重点,其中初期支护及时闭合和合理辅助工法的选取是关键.

Study on Dynamic Deformation Rules and Control Technology of Surrounding Rock for Tunnel

Based on existing research results and the Japanese Guipu tunnel surrounding rock deformation test, and combined with Zhengzhou-Xi＇ an Passenger Dedicated Line＇s engineering practice of large deformation of loess tunnel surrounding rock in the large cross section, this paper elaborates the dynamic deformation rules of surrounding rock deformation under the influence of tunnel construction, proposes the technical points and measures for surrounding rock deformation control and makes the appropriate recommendations. The results indicate that： after excavation, the deformation can be divided into three forms： displacement in front of the tunnel face, on the tunnel face and behind the tunnel face; and these displacements occur simultaneously. The controlling of the excavation face instability, unstable vault, arch springing submersion and large deformation is the key factor for tunnel surround- ing rock deformation control. Excavation process control and auxiliary construction method control is the emphasis; especially how to close the primary support timely and how to select auxiliary construction method reasonably are the crucial point.