以探索生活污染对黏性土物理力学性质的影响特征为目的,以浸泡试验和土工试验为技术手段,制备不同浓度的NaCl、Na:CO,和NH。C1污染黏性土,测定污染黏性土的塑性、渗透性、压缩性和抗剪性随污染浓度变化的规律,探讨被污染黏性土物理力学性质的演变机制。研究表明:黏性土遭受NaCl和Na,CO,污染过程中,塑性和压缩性提高,渗透性和抗剪性降低;黏性土遭受NH。C1污染过程中,塑性和压缩性降低,渗透性和抗剪性提高;黏土遭受生活钠铵盐污染过程中水理力学性质变化率明显高于粉质黏土;生活污染物通过改造黏粒表面“双电层”结构,影响黏性土的水理力学性质。
The objective of this study is to investigate the effect of domestic pollution on hydrophysical and mechanical properties of cohesive soils. Initially, cohesive soils polluted by various concentrations of sodium chloride (NaC1) , sodium carbonate (Na2CO3 ) and ammonium chloride (NH4C1) were precisely prepared through immersion tests. Then, the variation of plasticity, permeability, compressibility and shear strength of polluted cohesive soils with increasing pollution degrees was determined through geotechnical tests. Finally, the evolution mechanisms of the hydrophysical and mechanical properties of polluted cohesive soils were discussed. The study showed that an increase in plasticity and compressibility as well as a decrease in permeability and shear strength of cohesive soils was caused by the pollution of NaC1 and Na2CO3. Conversely, a decrease in plasticity and compressibility as well as an increase in permeability and shear strength of cohesive soils was contributed to the pollution of NH4C1. Meanwhile, the variation rate of the physical and mechanical properties of clay was much higher than that of silty clay. Domestic pollutants might provide an important effect on the hydrophysical and mechanical properties through the transformation of the double electrode layer structure on clay particles.