Slurry support, which is established by slurry infiltration, is essential to drilling with a slurry shield. In highly permeable soils, the slurry penetrates the ground and the required support force cannot be built up. Hence, large particles are usually added to the slurry to form filter cakes so that the slurry pressure can be applied on the excavation face successfully. In this paper, a series of penetration tests were carried out in which bentonite slurries with and without silt or sand were tested in different sandy grounds to investigate the influence of large particles on the slurry infiltration process. The commonly used apparatus was optimized structurally and operationally. The two distinct stages (i.e., mud spurt and filter cake formation) in the curves of discharged fluid in the penetration tests as well as the inflection point were analyzed. The elementary stable point, which is determined by the permeability of the filter cake, was proposed to identify the inflection point. Considering the clogging behavior of the slurry particles and the filtering ability of the ground, the particle retention rate (λ) was proposed to evaluate the degree of match between the slurry and the ground. The relationship between λ and the key index of the filter cake formation process was revealed. Based on the results of the tests in this paper, it is suggested to carry out infiltration tests and draw the curves (i.e., V_e-λ, T_s-λ, C-λ) and then identify the degree of match between the slurry and the ground, rather than directly use the value provided in this paper to make the identification.

通过泥浆渗透建立的泥浆支撑对于使用泥浆护罩进行钻井是必不可少的。在高渗透性土壤中，泥浆渗入地面，无法建立所需的支撑力。因此，通常将大颗粒添加到泥浆中形成滤饼，从而成功地将泥浆压力施加到开挖面。在本文中，进行了一系列渗透测试，其中在不同的沙地中测试了含粉和不含粉砂的膨润土浆液，以研究大颗粒对浆液渗透过程的影响。常用设备在结构和操作上都得到了优化。两个不同的阶段（即 对渗透试验排出流体曲线中的泥浆喷射和滤饼形成以及拐点进行了分析。提出了由滤饼渗透率决定的基本稳定点来识别拐点。考虑泥浆颗粒的堵塞行为和地面的过滤能力，颗粒截留率（λ ) 被提议用来评估泥浆和地面之间的匹配程度。揭示了λ与滤饼形成过程关键指标的关系。根据本文的试验结果，建议进行渗透试验并绘制曲线（即V _e - λ，T _s - λ，C - λ），然后确定泥浆之间的匹配程度和地面，而不是直接使用本文提供的值进行识别。