Przyczynek do poznania wpływu cech gruntu na procesy filtracji

Abstract

Przedstawiono wyniki laboratoryjnych badań filtracji w gruntach nasyconych i nienasyconych wodą.W ośrodku całkowicie nasyconym filtracja przebiega bardziej stabilnie niż w częściowo nasyconym, przy czym istotą rolę mają cechy strukturalne gruntu wynikające z jego genezy, głównie równomierność uziarnienia i kulistość. CONTRIBUTION TO THE KNOWLEDGE OF INFLUENCE OF SOIL PROPERTIES ON THE PERCOLATION PROCESSES The studies on percolation were often showing dependence of that process on nature of flow (laminary, turbulent, or mixed) as well as degree of soil saturation. In the present case, the degree of saturation is meant as a part of pore space infilled with water.Taking the above premises into account, there were conducted laboratory studies on the course of percolation in dependence on the following features of soils: grain size, sorting, sphericity and roundness of grains, and porosity. The tests involved percolation proceeding under conditions of full saturation and stable or varying hydraulic gradient, and – in the case of studies on capillary water absorption and, subsequently, zonal drainage – under conditions of incomplete saturation.Percolation parameters appeared fairly stable under drainage conditions and similar under conditions of stable and unstable percolation. In turn, the parameters were found to be markedly varying under conditions of incomplete saturation. The disturbances are greater in poorly sorted soils, weakly porous and with low sphericity of grains. Capillary effects are also higher in soils with such properties.The similarities suggest marked significance of capillary waters under conditions of incomplete saturation (e.g. during drainage).