为了确定酸污染对红黏土物理力学性质的影响,使用盐酸溶液对柳州地区红黏土进行浸泡,分析浸泡后红黏土的物理力学指标的变化,试验结果表明:随着浸泡的时间及浓度的增加,土中黏粒百分含量和液塑限增大,而比表面积和游离氧化铁含量降低;由于浸泡后柳州土的孔隙比有较大增加,压缩系数和渗透系数增大。对试验结果分析后认为,土性的变化源于强酸环境中游离氧化铁等物质发生溶解引起土体团粒崩解,黏粒的双电层及微观组构类型均发生了显著改变,各种物理力学指标是微观变化的宏观响应。
In order to determine acidic pollution impact on the physical and mechanical properties of lateritic clay,laboratory tests have been carried out on the lateritic soil from Liuzhou which was soaked by hydrochloric acid. The results show that the content of clay fraction,plastic limit and liquid limit increase with the increase of the solution concentration and soaking time in hydrochloric acid,however,specific surface area and free iron oxide decrease. Compressibility and permeability of Liuzhou soil increase as its void ration increases after soaking. The change of soil properties resultsfrom the free iron oxide dissolved in acid environment,which causes soil granule disintegration with significant change of double electric layer of clay and classification of microstructure. The physical and mechanical indexes are the macroscopic response to the micro change.