冻融循环对黄土物理力学性质影响的试验  

Experiment of impact of freezing-thawing cycle on physico-mechanical properties of loess

作　　者：毕贵权[1,2] 张侠[1,2] 李国玉[2] 马巍[2] 毛云程[2,3] 穆彦虎[2] 

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000 [3]甘肃省交通科学研究所有限公司,甘肃兰州730050

出　　处：《兰州理工大学学报》2010年第2期114-117,共4页Journal of Lanzhou University of Technology

基　　金：国家自然科学基金(40801022;40821001);中国科学院西部行动计划项目(KZCX2-XB2-10;KZCX2-YW-Q03-04)

摘　　要：通过补水条件下的冻融循环试验,研究冻融循环作用对黄土样的水分分布、变形和干密度的影响.试验结果表明:反复的冻融循环作用使得土样含水量增加,从底板到顶板土样含水量逐渐递增,冻融界面附近含水量变化梯度较大;黄土样在冻融循环初期冻胀变形比较剧烈,之后总体变形趋于稳定,冻融循环后期土样出现较小的沉降变形;冻融循环使得黄土样的干密度逐渐减小,且冻融循环剧烈的上部干密度较下部更小.By means of freezing-thawing cyclic test with water supplement,the impact of freezing and thawing actions on deformation,water redistribution and dry dense of loess samples was studied.The experimental result showed that repeated freezing and thawing actions would make the water content in samples increased gradually from the bottom to the top.It changed sharply near the interface between frozen and unfrozen areas.At the starting of freeze-thaw cycle,the frost heave of loess samples was stronger.Then the overall deformation became stable,which meant that the deformation induced by frost heave was equal to that inducted by thaw settlement.At the end of freeze-thaw cycle,there was a small settlement in samples,which resulted probably from soil particle rearrangement caused by strong freezing and thawing action.In addition,freezing and thawing actions decreased gradually the dry density of loess samples.The dry density in upper part was larger than that in bottom part.

关 键 词：黄土 冻融循环 冻胀 融沉 变形 含水量 干密度 

分 类 号：U216.417[交通运输工程—道路与铁道工程]