滨海氯盐渍土溶陷及盐胀特性  

Melt sinking and salt-heaving characteristics of coast chlorine saline soil

作　　者：魏进[1] 杜秦文[1] 冯成祥[2] 

机构地区：[1]长安大学公路学院,陕西西安710064 [2]天津市市政工程研究院,天津300051

出　　处：《长安大学学报（自然科学版）》2014年第4期13-19,共7页Journal of Chang’an University(Natural Science Edition)

基　　金：中央高校基本科研业务费专项资金项目(2013G1211011)

摘　　要：为了深入研究滨海氯盐渍土的溶陷和盐胀特性,在不同初始含水量、含盐量及上覆荷载条件下,进行了室内溶陷试验研究,完成了4次降温-升温循环下的盐胀试验,得到了不同含盐量试样的冻融循环盐胀规律,并通过改变荷载条件,对比分析了无荷和有荷情况下的盐胀规律。研究结果表明:影响氯盐渍土溶陷性质的主要因素是初始含水量和含盐量,初始含水量较小时,土样溶陷的敏感度更强,其溶陷系数较大;随着含盐量增大,不同荷载条件下的溶陷系数均表现为抛物线趋势,当含盐量为10%时,溶陷系数曲线出现明显的峰值;5℃^-10℃的降温区间是盐胀量迅速增大期;冻融循环条件下,盐渍土出现残余盐胀量,并表现盐胀累加性,累加性随着冻融循环次数的增多而减弱;上覆荷载对盐胀有明显的抑制作用,荷载作用使起胀温度大大提高,说明荷载对盐胀的发展有延缓作用。In order to explore the melt sinking and salt-heaving characteristics of coast chlorine saline soil, the laboratory collapsibility tests were carried out under conditions of different initial water content, different salt content, different freezing and thawing cycles and different loads; the salt-heaving tests un- der four freezing and thawing cycles were carried out to get the salt-heaving laws under freezing and tha- wing cycles of soil samples which have different salt content; the salt-heaving laws under load and non- load were compared and analyzed. The results show that the major influence factors of the melt sinking are initial water content and salt content. The sensitivity of melt sinking is lower and the coefficient of collapsibility is bigger when the initial moisture content is lower. The coefficient of collapsibility curves is parabola with the increase of the salinity. The curves of subsidence coefficient achieves to obvious peaks when the salt content is 10 ~. The rapid increasing period of the salt-heaving quantity was 5 ℃ to --10 ℃ cooling period, the residual salt-heaving capacity and the accumulativeness of salt-heaving are found after freezing and thawing cycles, and the accumulativeness is found which weakens with the increase of freezing and thawing cycle times. The load can obviously depress the salt-heaving,and can also delay the salt-heaving because it raises the salt-heaving temperature. 4 tabs, 9 figs, 16 refs.

关 键 词：道路工程 氯盐渍土 冻融循环 上覆荷载 溶陷 盐胀 

分 类 号：U416.16[交通运输工程—道路与铁道工程]