摘要
通过固化技术对盐渍土进行改良,使其成为优良的路基填料对于工程建设和保护环境等具有重要意义。以轻质固化盐渍土为研究对象,利用真三轴仪开展室内试验研究,分析了中主应力比、含盐量和围压对其应力-应变关系、破坏强度及抗剪强度指标的影响,揭示了轻质固化盐渍土强度破坏模式,并建立了强度指标计算方法。试验结果表明:应力-应变曲线斜率会随着中主应力比及围压的增大而增大,含盐量对其影响较小;含盐量对破坏应力的影响显著,当含盐量为4%时,破坏应力达到最大;不同条件下,轻质固化盐渍土会产生侧胀、锥形、斜裂、对角线的强度破坏形式;通过分析计算,建立了考虑中主应力比及含盐量等因素的轻质固化盐渍土破坏强度及抗剪强度指标的预测公式;通过对比表明Mohr-Columb强度准则描述轻质固化盐渍土强度偏于保守,容易低估土体的实际强度。研究成果可为工程实践提供参考。
It is of great significance for engineering construction and environmental protection to improve saline soil by curing technology to make it an excellent roadbed filler.In this paper,taking light solidified saline soil as the research object,laboratory tests were carried out by using true triaxial apparatus.The effects of the ratio of intermediate principal stress,salt content and confining pressure on the stress-strain relationship,failure strength and shear strength index were analyzed.The strength failure mode of light solidified saline soil was revealed and the calculation method of strength index was established.The test results showed that the slope of the stress-strain curve increases with the increase in the ratio of the intermediate principal stress and the confining pressure,but the salt content has little effect on it.The salt content has a significant effect on the failure stress.When the salt content is at 4%,the failure stress reaches the maximum.Under different conditions,the light solidified saline soil could produce different strength failure modes of lateral expansion,taper,oblique crack,and diagonal.Through analysis and calculation,the prediction formula of failure strength and shear strength index of light solidified saline soil considering the ratio of intermediate principal stress and salt content was established.The comparison showed that the Mohr-Columb strength criterion is conservative in describing the strength of light solidified saline soil and it tends to underestimate the actual strength of the soil.The research results can provide references for engineering practice.
作者
杨爱武
杨少朋
郎瑞卿
陈子荷
YANG Ai-wu;YANG Shao-peng;LANG Rui-qing;CHEN Zi-he(School of Environmental Science and Engineering,Donghua University,Shanghai 201620,China;Tianjin Key Laboratory of Soft Soil Characteristics and Engineering Environment,Tianjin Urban Construction University,Tianjin 300384,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2021年第3期593-600,共8页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51978440)
天津市科技计划项目(No.19JCZDJC39700,No.2016CJ01)
天津市自然科学基金项目(No.19JCQNJC06900)。
关键词
轻质固化盐渍土
中主应力比
含盐量
破坏强度
抗剪强度指标
light solidified saline soil
intermediate principal stress ratio
salt content
breaking strength
shear strength index
