关键词: 孔径概率分布, 无纺土工布, 侧限单向拉伸, 孔径累积分布理论, 干筛试验, 特征孔径

Abstract: Nonwoven geotextiles used as filters are commonly subjected to laterally constrained tensile loads in practice. A theoretical solution is developed to study the pore size distribution of nonwoven geotextiles under laterally constrained uniaxial tension. The theoretical solution is based on a fiber network model, whereby the probabilistic sieving problem is equivalent to a mass-based probability of retention which is modified from a number-based probability density. Three different needle-punched nonwoven geotextiles are subjected to the uniaxial tensile strains with lateral confinement. The pore sizes of unstrained geotextiles and geotextiles under strains 3%, 5% and 10%, respectively, are obtained from dry sieving test after eliminating electrostatic effects. The experimental results present an accurate prediction of theoretical equations in pore size distribution with laterally constrained uniaxial tensile strain. The pore size distribution curves move towards right with the increase of tensile strain under lateral confinement, which results in the increase in characteristic pore diameters.

Key words: pore size probability distribution, nonwoven geotextile, laterally constrained uniaxial tension, cumulative pore size distribution theory, dry sieving test, characteristic pore size