通过室内砂槽模型试验模拟均质无黏性土垂向流土的发生发展过程,研究无黏性土发生渗透变形和渗透破坏过程中,土体渗透系数、水力梯度、渗透流量等参数的变化规律,分析土体渗透变形过程中优势流的产生、发展的循环过程,并通过对比试验研究了发生流土破坏后的土体经过一段时间自重固结后的抗渗强度。试验结果表明:均质无黏性土在渗流作用下发生渗透变形的过程中,有一个渗透系数不变的阶段。这一阶段土体中还没有形成优势流,土体处于稳定的安全渗流阶段。土体中优势流的空间可变性造就了一个优势流“形成→发展→消失→再形成”的循环过程,这种循环过程伴随着土体中不断的微小渗透变形。土体发生流土破坏后,破坏区域的土体出现了水力筛分现象,水力筛分过程改变了土体结构,降低了土体的抗渗强度。 Through the indoor sand tank model test, simulating the occurrence and development of vertical flow soil with homogeneous non-cohesive soil, the change of permeability coefficient, hydraulic gradient and permeate flux of soil in the process of seepage deformation and infiltration of non-cohesive soil were studied Law, and analyzed the cycle of the generation and development of the dominant flow in the process of soil infiltration and deformation, and studied the anti-seepage strength of the soil after self-weight consolidation by the comparative test. The experimental results show that there is a constant permeability coefficient in the process of seepage deformation of homogeneous clayey soils under seepage. In this stage, no dominant flow has been formed in the soil and the soil is in a stable safe seepage stage. The spatial variability of the dominant flow in the soil creates a cycle of the dominant flow “formation → development → disappearance → reformation”. This cyclic process is accompanied by the continuous micro-infiltration deformation in the soil. After soil failure occurs, the soil in the damaged area appears the phenomenon of hydraulic screening. The hydraulic screening process changes the soil structure and reduces the seepage resistance of the soil.