ABSTRACT

The permeability of soil is a fundamental parameter in hydrological and geotechnical studies, nevertheless, the investigations on the silt especially the heavy mental contaminated silt have rarely been reported. The research introduces the effect of the different factors, including the osmotic pressure, curing time, the content of binders and the concentration of lead, on the permeability and microscopic properties of lead-contaminated silt, which is solidified by a novel curing agent, formed by mixing cement, fly ash and desulphurization gypsum (CFG). According to the tests of the permeability and scanning electron microscope (SEM), the permeability of samples is investigated under different influencing factors. The results demonstrate that the permeability coefficient of the contaminated silt increases with the increasing osmotic pressure and lead ion concentration, while decreases with the increasing CFG content and the curing time, additonally, there are interactions among various factors, which jointly affect the permeability of samples. Moreover, the statistical analysis shows that osmotic pressure has the most significant effect on permeability among various factors. Besides, the influence of lead ion concentration, osmotic pressure and CFG content on the permeability coefficient at the curing time of 14d is more significant than that of 28d, and the influence order of factors was slightly different at different curing time. Furthermore, the SEM test proves the conclusion of the statistical analysis, which also explains the common reasons for the enhancement of the impermeability and unconfined compressive strength (UCS) of the lead-contaminated silt with the increasing curing time.

摘要

土壤的渗透性是水文和岩土研究中的一个基本参数，然而，关于淤泥特别是重度金属污染淤泥的研究却鲜有报道。研究介绍了渗透压、固化时间、粘结剂含量和铅浓度等不同因素对铅污染淤泥的渗透性和微观性能的影响。通过混合水泥、粉煤灰和脱硫石膏 (CFG)。根据渗透率和扫描电镜（SEM）测试，考察了不同影响因素下样品的渗透率。结果表明，污染淤泥的渗透系数随着渗透压和铅离子浓度的增加而增加，随着CFG含量和固化时间的增加而减小，此外，各因素之间存在相互作用，共同影响样品的渗透率。 . 此外，统计分析表明，渗透压对渗透率的影响是各因素中最显着的。此外，铅离子浓度、渗透压和CFG含量对渗透系数的影响在14d养护时间比28d更显着，不同养护时间各因素影响顺序略有不同。此外，SEM 测试证明了统计分析的结论，