冻融循环下加筋膨胀土边坡稳定性模型试验  

Model Test of Reinforced Expansive Soil Slope Stability in Freeze-Thaw Cycles

作　　者：吕建航 杨忠年[1] 时伟[1] 李国玉 凌贤长[1,3] 张莹莹 LüJianhang;Yang Zhongnian;Shi Wei;Li Guoyu;Ling Xianzhang;Zhang Yingying(School of Civil Engineering,Qingdao University of Technology,Qingdao 266033,Shandong,China;State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;School of Civil Engineering,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]青岛理工大学土木工程学院,山东青岛266033 [2]中国科学院西北生态环境资源研究院冻土工程国家重点实验室,兰州730000 [3]哈尔滨工业大学土木工程学院,哈尔滨150001

出　　处：《吉林大学学报（地球科学版）》2021年第5期1587-1596,共10页Journal of Jilin University：Earth Science Edition

基　　金：冻土工程国家重点实验室开放基金项目(SKLFSE201601);山东省泰山学者专项基金项目(2015-212);国家重大科研仪器开发基金项目(41627801)。

摘　　要：控制边坡在冻融循环中的劣化作用,可保障季节冻土区域膨胀土边坡长期稳定。为确定土工格栅对膨胀土边坡在冻融循环过程中的稳定效果与工程意义,本文开展了膨胀土边坡模型试验,对比冻融过程中边坡内土压力、含水率、位移、温度变化。结果表明:土工格栅可约束膨胀土冻融裂缝,使裂缝发育更为均匀一致,同时减小边坡位移;加筋材料能抑制边坡水分迁移与热传导并减小土压力变化;对膨胀土边坡加筋处理可显著降低含水率波动幅值,从而减小膨胀土受含水率变化引发的胀缩劣化;不同于普通黏土,膨胀土边坡冻融循环中呈现冻缩融胀特点,而边坡加筋可有效提升冻土区膨胀土边坡的冻融稳定性,具有工程应用价值。China has a large area of frozen soil, and the long-term stability of the expansive soil slopes in the seasonal frozen area can be guaranteed by controlling the deterioration of the slopes in freezing and melting cycles. In order to determine the role of geogrid in the stability of the expansive soil slopes during the freeze-thaw cycle, the model test of the expansive soil slope is carried out in this paper. The results show that: 1)The geogrid can restrain the freeze-thaw cracks of expansive soil, make the crack development more uniform, and reduce the slope displacement;2)The reinforced material can inhibit the water migration and heat conduction of the slope and reduce the change of soil pressure;3)The reinforced treatment of expansive soil slope can significantly reduce the fluctuation of water content, so as to reduce the swelling and shrinking of expansive soil caused by the change of water content;4)Different from ordinary clay, the expansive soil slopes show the characteristics of freeze shrinkage and thaw expansion in the freeze-thaw cycle, and the slope reinforcement can effectively improve the freeze-thaw stability of expansive soil slopes in frozen soil areas, which has engineering application value.

关 键 词：膨胀土 边坡稳定性 边坡加筋 冻融循环 裂缝 

分 类 号：P642.2[天文地球—工程地质学]