Salinity and Clay Mineralogy Effects on Consolidation Behavior of Pure Clays
Pure clays or sand-clay mixtures with different clay mineral are widely used in liners or vertical barriers of waste landfill,and the pore water was characterized by its high salinity in coastal area.Thus,it is essential to understand the salinity effects on their consolidation behavior.In this study,oedemeter and SEM tests were conducted on four pure clays with different mineralogy.Several aspects of soil behavior,such as compression index,the end of primary consolidation stage and micro-structure,were investigated in view of pore water salinity effect.The results show that higher ionic concentration significantly decreases the compression index Cc and liquid limits(LL)for clays containing montmorillonite.While the period of primary consolidation was shorten under the impact of water salinity.For kaolinite with or without sodium chloride,a similar Cc,LL and the ending time of primary consolidation stage tp were observed.In view of flocculation,the salinity effect on consolidation behavior was interpreted.Increasing in salinity allows a flocculation and particle readjustment at constant water content for montmorillonitic clay.Then,larger inter-particle spaces and effective void ratio increased the permeability and decreased the drainage period,and larger internal frictions decreased the compression index Cc and LL.
Pure clays Water salinity Clay minerals Consolidation behaviour Micro-structure
Tongwei Zhang Yongfeng Deng Haocheng Xue Xingjun Zhang Shijun Wang
Key Laboratory of Mechanics on Disaster and Environment in Western China,College of Civil Engineerin Institute of Geotechnical Engineering,Transportation College,Southeast University,Nanjing,China Gansu Henlu Transportation Survey and Design Co.,Ltd.,Lanzhou,China Economy and Technology Research Institute,State Grid Gansu Electric Power Company,Lanzhou,China
国际会议
The 8th International Congress on Environmental Geotechnics(第八届国际环境土工大会)
杭州
英文
529-536
2018-10-28（万方平台首次上网日期，不代表论文的发表时间）