非饱和盐渍土三轴蠕变试验与模型分析  

Triaxial creep test and model analysis of unsaturated saline soil

作　　者：余云燕[1] 罗崇亮 王堃[1] 岳建平[1,2] 高纯 田小鹏 张睿承 薛鹏 Yu Yunyan;Luo Chongliang;Wang Kun;Yue Jianping;Gao Chun;Tian Xiaopeng;Zhang Ruicheng;Xue Peng(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;School of Civil Engineering,Hexi University,Zhangye 734000,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070 [2]河西学院土木工程学院,张掖734000

出　　处：《东南大学学报（自然科学版）》2022年第4期704-711,共8页Journal of Southeast University：Natural Science Edition

基　　金：甘肃省科技计划资助项目(21YF5GA050);甘肃省教育厅产业支撑计划资助项目(2021CYZC-28);甘肃省交通运输厅科技研发资助项目(2021-12);甘肃省基础研究创新群体资助项目(21JR7RA347).

摘　　要：为研究非饱和盐渍土的蠕变行为,开展了一系列三轴固结不排水蠕变试验,分析了不同加载应力、含盐量及压实度下的蠕变特性,并采用修正前、后的Singh-Mitchell蠕变模型对非饱和盐渍土蠕变行为进行预测.结果表明:蠕变曲线呈三阶段发展,稳态蠕变阶段的蠕变速率趋于0;应力应变等时曲线呈非线性的曲线簇由密向疏发展,长期强度在100~150 kPa范围内,为瞬时强度的0.39~0.73倍;加载应力、压实度、w(NaCl)对其蠕变特性有显著影响;修正后的Singh-Mitchell蠕变模型不仅克服了原Singh-Mitchell蠕变模型的应力局限性,还可有效预测非饱和盐渍土三轴蠕变行为.To study the creep behaviors of unsaturated saline soils,a series of triaxial consolidation undrained creep tests were conducted to analyze the creep characteristics under different loading stresses,salt contents and compaction degrees.The creep behaviors of unsaturated saline soils were predicted by using the original Singh-Mitchell creep model and the modified one.The results show that the creep curve shows a three-stage development,and the creep rate tends to zero at the steady-state creep stage.The stress-strain isochronous curve develops in a nonlinear cluster from dense to sparse.The long-term strength is in the range of 100 to 150 kPa,and is 0.39 to 0.73 times of the instantaneous strength.The loading stress,the compaction and w(NaCl)have significant effects on the creep properties.The modified Singh-Mitchell creep model can overcome the stress limitations of the original Singh-Mitchell creep model,and predict the triaxial creep behaviors of unsaturated saline soils.

关 键 词：非饱和盐渍土 三轴蠕变试验 应力-应变等时曲线 修正Singh-Mitchell蠕变模型 

分 类 号：TU411[建筑科学—岩土工程]