Abstract

Studies on grout consolidation after synchronous grouting around shield tunnels have ignored the expansion of the grout–groundwater interface and the difference in the permeabilities of the grout and water in the stratum. The process of grout pressure dissipation and diffusion in the stratum was solved with a two-dimensional two-phase seepage model, with which the head losses caused by grout diffusion in the stratum and groundwater seepage in the stratum under the ‘push-displacement effect’ were studied together. In addition, the influence of the temporal variation in viscosity and the infiltration effect were considered. Then, a two-phase analytical seepage model of consolidation for shield grouting considering the temporal variation in viscosity and the infiltration effect was established. A numerical algorithm was designed to solve the theoretical model with the difference method. The analytical model was verified by comparison with the results of numerical simulation. Furthermore, the main parameters in the analytical model were analysed. The results show that the temporal variation in grout viscosity and the infiltration effect greatly influence the stable pressure value and the loss rate of the volume of grout after consolidation. Among the main parameters in the model, the permeability coefficient of the stratum is the most sensitive.

摘要

盾构隧道周边同步注浆后的浆液固结研究忽略了浆液-地下水界面的扩大以及地层中浆液与水的渗透率差异。采用二维两相渗流模型求解地层中浆液压力消散扩散过程，在“推-驱效应”作用下，地层中浆液扩散引起的水头损失和地层地下水渗流。一起研究过。此外，还考虑了粘度随时间变化的影响和渗透效果。然后，建立了考虑黏度随时间变化和入渗效应的盾构注浆固结两相渗流分析模型。设计了一种数值算法，用差分法求解理论模型。通过与数值模拟结果的比较，验证了解析模型。此外，分析了分析模型中的主要参数。结果表明，浆液粘度的时间变化和入渗效果对稳定压力值和固结后浆液体积的损失率有很大影响。在模型的主要参数中，地层的渗透系数最为敏感。结果表明，浆液粘度的时间变化和入渗效果对稳定压力值和固结后浆液体积的损失率有很大影响。在模型的主要参数中，地层的渗透系数最为敏感。结果表明，浆液粘度的时间变化和入渗效果对稳定压力值和固结后浆液体积的损失率有很大影响。在模型的主要参数中，地层的渗透系数最为敏感。