摘要
基于对易溶盐溶解是发生溶陷变形根本原因的认识,对黄土湿陷试验进行扩展,开展了不同Na Cl含量的伊犁原状黄土样的原含水率、浸纯水和浸饱和Na Cl溶液三种黄土压缩试验,实现了湿陷和溶陷的区分,探究了Na Cl含量对压缩、湿陷和溶陷特性的影响规律。研究结果表明:通过以上三种试验能很好地区分湿陷和溶陷,当Na Cl含量较小时,湿陷作用较大,随Na Cl含量的增加,影响变形的主导作用由湿陷作用逐渐转向溶陷作用,当Na Cl含量为10 g/kg左右时两种作用基本相等;随Na Cl含量的增加,峰值溶陷系数呈幂函数增加,峰值湿陷系数呈线性减小,起始溶陷压力呈指数降低;施加垂直压力后,试样高度呈先陡后缓的减小趋势,变形稳定时间随垂直压力的增大而增长。
Based on the understanding that the dissolution of soluble salt is the root cause of salt collapsible deformation,three kinds of loess compression tests are carried out on undisturbed Ili loess samples with different Na Cl contents,namely,original water content,soaked in pure water and saturated Na Cl solution,which is an extension of loess collapsibility test.The difference between water collapse and salt collapse is achieved,and the influences of Na Cl content on the characteristics of compression,water collapsibility and salt collapsibility are investigated.The results show that the above three kinds of tests can well distinguish the water collapse and salt collapse.When the Na Cl content is small,the water collapse is greater,and with the increase of Na Cl content,the leading role of deformation is gradually changed from the water effect to the salt effect.When the Na Cl content is about 10 g/kg,the two effects are almost equal.With the increase of Na Cl content,the peak salt collapse coefficient increases as a power function,while the peak water collapse coefficient decreases linearly and the starting pressure of salt collapse decreases exponentially.When the vertical pressure is applied,the height of the sample decreases from steeply to slowly,the time of deformation stabilization increases with the increase of vertical pressure.
作者
牛丽思
张爱军
王毓国
韩婧文
赵佳敏
胡锦方
NIU Li-si;ZHANG Ai-jun;WANG Yu-guo;HAN Jing-wen;ZHAO Jia-min;HU Jin-fang(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2020年第S02期67-71,共5页
Chinese Journal of Geotechnical Engineering
基金
国家重点研发计划项目(2017YFC0405103)
国家自然科学基金面上项目(51978572)
陕西省重点研发计划项目(2017ZDXM-SF-074)
陕西省水利科技计划项目(2013slkj-10)
关键词
伊犁黄土
NaCl含量
湿陷
溶陷
变形
Ili loess
NaCl content
water collapse
salt collapse
deformation
作者简介
牛丽思(1990—),女,博士研究生,主要从事非饱和黄土试验研究工作。E-mail:lisi_niu@sohu.com;通信作者:张爱军(E-mail:zaj@nwsuaf.edu.cn)
