厦门海底隧道建设中涌水量流固耦合数值模拟

Coupled fluid-mechanical numerical simulation on water inflow capacity in Xiamen subsea tunnel during construction

文章运用有限差分软件(FLAC3D)对厦门海底隧道F4风化深槽的涌水情况进行了流固耦合分析。由于隧道在穿越风化深槽段时采用双侧壁导洞法施工,因此对隧道施工三个阶段的涌水量分别进行了分析,并对不同注浆密度下的涌水量进行了对比。研究结果表明,在隧道开始开挖阶段,涌水量较大,之后逐渐趋于稳定;左右侧导洞开挖时,涌水量逐渐增大,但隧道中间部分开挖后,涌水量有所降低;数值计算所得涌水量结果与规范推荐公式计算结果基本一致。

The fluid - mechanical analysis on water inflow capacity in Xiamen subsea tunnel was carried out by the finite differences software FLAC3D. Since two side headings were driven when the tunnel traversed the F4 weathered deep trough, the water inflow capacity in three different construction stages and under different grouting intensity were analyzed. The results showed that the water inflow was great at the beginning of excavation, later on the water inflow became steady. When both side headings were driven, the water inflow capacity increased gradually. After the middle portion was excavated, the water inflow capacity decreased. The water inflow capacities obtained by the numerical analyses were well consistent with the results of calculation according to the code.