流沙层动水注浆扩散仿真研究

Numerical Simulation of Dynamic Grouting in Drift Sand Strata

在地下工程施工中,常常会遇到流沙层,导致工程受阻。通过注浆胶结作用加固流沙层是目前广泛应用的施工方法。然而国内外对流沙层注浆的研究大多处在经验总结阶段。针对上述问题,为得到流沙层动水注浆三维扩散一般规律,基于流体两相渗流理论,建立了流沙层多孔介质中浆液-水的两相渗流公式,并应用有限元分析软件COMSOL进行了三维建模仿真。仿真结果表明:浆液在渗流场中大致呈钟形分布且存在逆水流扩散区域,浆液与水之间没有明显的分界面而是存在一个过渡区;浆液的粘度越低扩散范围越大,粘度越高扩散范围越小,注浆压力越大,浆液扩散范围越大。研究结果为加固流水层提供了科学参考。

In underground engineering, project is often blocked from the sand strata. Grouting method is widely used in reinforcement of the sand strata. However, research on grouting in sand strata mostly relies on engineering experience. Theoretical study and mathematical simulation rarely come into practice. In order to gain basic laws of dynamic water grouting diffusion in drift sand strata, we established a slurry-water two-phase flow formula based on two -phase theory. 3-D modeling simulation was implemented based on COMSOL Multi-physics. The results show that slurry distribution in the seepage field forms a bell shape and shows an upstream diffusion region. The interface between slurry and water shows no obviousness but a transition zone. The lower the viscosity of the slurry is, the wider the diffusion range. The higher the grouting pressure is, the bigger the diffusion range.