关键词: 泥浆, 地层, 渗透特性, 渗透流量, 泥皮

Abstract: Supporting the excavation face is the most important role for slurry in the field of engineering, such as diaphragm walls, bored piles, and slurry shield tunneling. To achieve the function, a filter cake has to be formed on the soil, and the soil and pore water pressure have to be counteracted by slurry pressure. And the essence of filter cake formation is that the slurry infiltrates in the stratum. To reveal the phenomena and laws of slurry infiltrating into the soils, a series of slurry infiltration tests is carried out on sand samples with different permeabilities. Based on the test results, three typical seepage curves are discovered, and the shapes of slurry particles accumulated on the ground surface are also divided into three types: filter cake, filter cake with an infiltrated zone, and only an infiltrated zone without filter cake. Meanwhile, a corresponding relationship is discovered between the types of slurry seepage curves and the shapes of slurry particles accumulated on the surface. In addition, the seepage discharge during slurry infiltrating into the sand reflects the type of slurry infiltration. And it can be used as a criterion to determine whether a filter cake is formed on the surface.

Key words: slurry, stratum, infiltration, seepage discharge, filter cake