基于流固耦合的隧道围岩稳定性分析

Stability Analysis of Tunnel Surrounding Rock Based on Fluid-solid Coupling Theory

为了研究大五山隧道的围岩稳定性规律,基于流固耦合理论建立了考虑埋深和周边水力补给条件的FLAC 3D隧道开挖模型,研究了流固耦合作用下隧道的稳定性规律,分析了隧道开挖过程中围岩的位移、水压、塑性区变化规律。研究结果表明:(1)隧道开挖影响下,掌子面前方10m范围内围岩出现明显位移,最大位移为拱顶处的23. 5mm;(2)掌子面周边20m范围内的围岩出现水压力下降,掌子面最大涌水量约为100m3h;(3)隧道围岩的塑性区呈v形,最大破坏区域出现在隧道两帮及顶部,为2m^4m。

In order to study the stability of the surrounding rock of Dawushan tunnel,a FLAC 3D tunnel excavation model considering the buried depth and surrounding hydraulic supply conditions was established based on the fluid-solid coupling theory.The stability of the tunnel under the fluid-solid coupling was studied,and the displacement,water pressure and plastic zone variation of the surrounding rock during the tunnel excavation was analyzed.The results indicate that:(1)Under the influence of tunnel excavation,the surrounding rock in the range of 10m in front of the tunnel face has obvious displacement,and the maximum displacement is 23.5 mm at the dome.(2)Water pressure decreases in surrounding rocks within 20m around the palm surface,and the maximum water inflow of tunnel face is about 100 m3/h;(3)The plastic zone of rock surrounding the tunnel is in a"v"shape,and the maximum failure zone appears on the two sides and the top of the tunnel,which is 2m-4m.