摘要
为研究罗布泊地区天然亚硫酸盐渍土盐-冻胀各冻融循环周期内的变化规律及影响因素,采用控制初始含水率和干密度的方法进行冻融循环试验。试验结果表明:亚硫酸盐渍土各周期的盐-冻胀率为先增后减的二次函数状,在冻融循环作用下盐溶液浓度降低,土体内部结构达到临界点,4周期后各周期的盐-冻胀率开始降低;前4周期的盐-冻胀率呈先减速后加速,且随含水率的增大表现明显,土体结构性损伤是盐-冻胀增长加速的主要原因;随初始干密度的增大,盐-冻胀作用在改变土体的孔隙和结构时所需的能量增加,试验中各周期的盐-冻胀率表现出波动性的变化。研究结果表明:亚硫酸盐渍土各冻融周期的盐-冻胀率与土体在各周期所呈现的结构状态有密切关系。
In order to analyze the Lop Nur area＇s sulfurous saline soil salt-frost expansion change rules and influences during each freeze-thaw cycle,we adopted the method of controlling initial water content and dry density to experiment the freeze-thaw cycle tests. The results indicate that the sulfurous saline soil＇s salt-frost expansion rate in each freeze-thaw cycle is a quadratic function,which firstly increases and then decreases. Under the influence of the freeze-thaw cycles,the salt solution＇s concentration decreases and the soil＇s interior structure reaches a critical point. The test indicates that after four cycles each cycle＇s salt-frost rate slows down. The growth rate of the early four circle stages for the salt-frost expansion accelerates after slows down,and this rule could be more obvious with the increase in water content. The damage of soil＇s structural could be the main reason for the early stage salt-frost heave rate increase. With the dry density increasing the energy for salt-frost which helps change the porosity and structure enlarged,and this experiment phenomenon shows the salt-frost heave rate of each cycle could be more unstable. The result proves that the sulfurous saline soil＇s salt-frost expansion in each freeze-thaw could have a close relation with the status of soil structure in different cycles.
作者
潘蕾
张远芳
陈敬知
张运海
PAN Lei, ZHANG Yuanfang, CHEN Jingzhi, ZHANG Yunhai(College of Hydraulic and Civil Engineering of Xinjiang Agricultural University, Urumqi 830052, Chin)
出处
《水资源与水工程学报》
CSCD
2018年第1期220-224,231,共6页
Journal of Water Resources and Water Engineering
基金
国家自然科学基金项目(41262012)
新疆农业大学研究生校级科研创新项目(XJAUGRI2016-031)
关键词
亚硫酸盐渍土
盐-冻胀变化规律
各冻融周期
结构性
sulfurous saline soil
salt -frost heave change rules
each freeze -thaw cycle
structural
