复合土工膜渗透性能试验研究

Experimental investigation of the permeability of composite geomembrane

摘要: 以高密度聚乙烯复合土工膜为试验材料,利用柔性壁渗透仪测定一定时间间隔通过复合土工膜的渗透量,通过计算求得复合土工膜的渗透系数,分析渗透系数随渗透压和渗透压应力路径的变化规律。利用扫描电子显微镜拍摄复合土工膜的照片,从微观结构上揭示了渗透系数变化的原因。试验结果表明:柔性壁渗透仪可以精确测定复合土工膜的渗透性能参数;复合土工膜在0.1MPa的有效应力作用下,渗透压从0.1MPa增大到0.6MPa的范围内,渗透系数有3种变化趋势,分别是渗透系数基本不变、渗透系数随渗透压的增大而增大和渗透系数随渗透压的增大而减小。复合土工膜物理性质的不均匀性和渗透通道的形态是影响防渗效果的主要因素。

Abstract: High density polyethylene composite geomembrane is used as a test material and the flexible wall permeameter is used to calculate the coefficient of the composite geomembrane.Changes in hydraulic coefficients with osmotic pressure and osmotic stress path are analysed.Scanning electron microscope photographs from microcosmic structure reveals the reason for the changes in hydraulic coefficients.The test results show that the flexible wall permeameter can accurately determine the geomembrane hydra...