基于流固耦合的强度折减法的地下水渗流对隧道稳定性的影响研究

Research on influence of groundwater seepage on tunnel stability based on strength reduction method of fluid-solid coupling

为充分研探讨地下水渗流对隧道稳定的影响,基于流固耦合的强度折减法优化计算隧道稳定性的安全系数。以3种计算工况参考,分别对地下水渗流、流固耦合计算模式下影响隧道稳定性的安全系数进行详细分析,并对地下水位对隧道安全系数和拱顶沉降进行了分析。结果表明,考虑地下水渗流情况后,隧道的安全系数降低;考虑流固间接耦合和完全耦合的模式计算获得的隧道安全系数大致相同,但间接耦合模式下消耗的计算时间最短;随着地下水水位的升高,隧道安全系数有所下降,二者呈线性相关;在选取相同折减系数时,隧道拱顶的沉降程度随地下水水位升高而增加。

In order to fully study and explore the influence of groundwater seepage on tunnel stability,this paper optimized and calculated the safety factor of tunnel stability based on the strength reduction method of fluid-solid coupling.With reference to three calculation conditions,the safety factors affecting the stability of the tunnel under the calculation mode of groundwater seepage and fluid-solid coupling were analyzed in detail.It also analyzed the influence of the underground water level on the safety factor of the tunnel and the settlement of the vault.The results showed that:the safety factor of the tunnel is reduced after considering the groundwater seepage;the safety factor of the tunnel calculated by considering the indirect fluid-solid coupling and the fully coupled mode is roughly the same,but the calculation time consumed in the indirect coupling mode is the shortest.With the increase of groundwater level,the tunnel safety factor decreases,and the two are linearly related;when the same reduction factor is selected,the settlement degree of the tunnel vault increases with the increase of the groundwater level.