水平层状围岩隧道顶板变形特征及机理分析

Analysis of Roof Deformation Characteristics and Mechanism in Horizontal Layer Rock Tunnel

隧道在开挖过程中,经常会经过水平层状围岩,这将给隧道施工带来很大的困难,造成安全事故。通过对水平层状围岩隧道顶板变形特征及机理分析得出:水平层状围岩在隧道顶板层面薄弱带附近由于不同步弯曲沉降产生分离,形成离层;水平岩层软硬相间,层间黏结力较差,隧道开挖后拱顶围岩稳定性较差,拱顶失稳几率较大;对于水平层状围岩地区要做好塌方的预防和初期处理,尽量做到预防为主。当发生事故时,要做好相应的措施,减少人员的伤亡。

The tunnel is often being tunneled through horizontal layer surrounding rock in process; which will bring great difficulties in the tunnel construction, causing accidents. Through the analysis of roof deformation characteristics and mechanism in horizontal layer rock tunnel, this paper concludes that the horizontal layer surrounding rock tunnel near roof level sync due to weak produced separation, bending settlement formed delamination. Levels between layers alternate with hard and soft rock strata and unbond force is poor, and the stability of surrounding rock tunnel excavation vault is poor. After tunneling, it＇s more likely to in- crease vaults＇ instability. For horizontal layer surrounding areas, we must complete collapse prevention and early treatment, and prevention is the main part. When the accident happens, proper measures should be done to reduce personnel casualties.