漠河地区冻结粉质黏土强度及其影响因素研究  

Study on the strength of frozen powdery clay and its influencing factors in the Mohe region

作　　者：戚春香[1] 马佳荟 路维龙 张凯强 赵中涛 QI Chunxiang;MA Jiahui;LU Weilong;ZHANG Kaiqiang;ZHAO Zhongtao(College of Transportation Science and Engineering,CAUC,Tianjin 300300,China)

机构地区：[1]中国民航大学交通科学与工程学院,天津3003000

出　　处：《中国民航大学学报》2025年第2期45-51,共7页Journal of Civil Aviation University of China

基　　金：国家自然科学基金面上项目(52278542);国家重点研发计划项目(2021YFB2600500)。

摘　　要：多年冻土受温度及冻融循环作用影响显著,为了探究其力学特性,本文以漠河地区冻土为研究对象,开展了不同含水率及冻融循环次数条件下的冻土直剪试验以及不同温度、含水率、围压、加载频率和冻融循环次数条件下的冻土动三轴试验,以分析不同影响因素下冻土的抗剪特性和动力性能。试验结果表明:冻土试样剪应力-剪切位移曲线为应变软化型;冻土试样随含水率和冻融循环次数增加,抗剪强度、黏聚力和内摩擦角均出现不同程度的降低;冻土试样的动弹性模量在试验内的变化范围为210~800 MPa,与含水率、冻融循环次数、加载频率呈正相关关系,与温度和围压条件呈负相关关系,并随含水率的变化最为显著。同时,根据试验结果得出基于各影响因素的冻土动弹性模量计算公式。以上研究成果可为漠河地区开展机场建设等工程项目提供冻土力学特性参考数据。Permafrost is significantly affected by temperature and freeze-thaw cycles.In order to explore its mechanical properties,this paper takes frozen soil in Mohe area as the research object,and conducts direct shear tests of frozen soil under different moisture content and freeze-thaw cycle times,as well as dynamic triaxial tests of frozen soil under different temperature,moisture content,confining pressure,loading frequency,and freeze-thaw cycle times,to analyze the shear resistance characteristics and dynamic performance of frozen soil under different influencing factors.The experimental results indicate that the shear stress and shear displacement curves of frozen soil samples are strain softening type.As the moisture content and freeze-thaw cycles increase,the shear strength,cohesion,and internal friction angle of frozen soil samples all decrease to varying degrees.The dynamic elastic modulus of frozen soil samples varies within the range of 210-800 MPa in the experiment,which is positively correlated with moisture content,freeze-thaw cycle times,and loading frequency,and negatively correlated with temperature and confining pressure conditions,with the most significant change with moisture content.Meanwhile,based on the experimental results,the formula for calculating the dynamic elastic modulus of frozen soil based on various influencing factors are derived.The above research results can provide reference data on the mechanical properties of frozen soil for airport construction and other engineering projects in the Mohe area.

关 键 词：多年冻土 抗剪强度 动弹性模量 冻融循环 含水率 

分 类 号：P642.14[天文地球—工程地质学] V351.1[天文地球—地质矿产勘探]