水平和竖向渗流情况下砾石土渗透性的对比分析

Comparative Analysis of Horizontal and Vertical Permeability of Clayey Gravelly Soil

目前对土料的渗透性和抗渗性能的试验研究多采用竖向渗透仪,土料水平方向的渗透试验开展得很少.然而,土料的水平方向的渗透性一般大于竖向,因此,土体中渗流的优势方向往往是水平方向.基于不同条件下的渗透试验结果,研究水平和竖向渗流情况下砾石土料渗透性的异同,分析探讨不同试验结果的差异及其影响因素.分析结果表明,不同的砾石含量、不同反滤料密度和级配情况下,水平渗透试验测得的试样的渗透性都大于竖向渗透试验的测值.两者的差异随砾石土的砾石含量、反滤料密度和颗粒尺寸的增大而增大.

Currently, vertical permeameter is widely used for investigation on the permeability and seepage re- sistance of soils, and horizontal permeability tests are rarely conducted. However, the horizontal permeability of soils is usually larger than the vertical permeability, so the dominant seepage direction in soils is commonly horizontal direction. Based on seepage tests under different conditions, the difference between the horizontal and vertical permeability of clayey gravelly soil are studied. The differences among different tests and their impact factors are analyzed and discussed. The results show that the permeability of the samples measured by horizontal permeability tests is larger than that obtained by vertical permeability tests whatever the difference of the gravel content of the clayey gravelly soil, the dry density and grading of the filter. The difference be- tween the horizontal and vertical permeabilities increases with the increases in the gravel content of the clayey gravelly soil, the dry density and grain size of the filter.