Research On Influencing Factors And Changing Laws Of Saline Soil And Frozen Soil Strength In Northeast China

The research area of this paper is Dulbert County,Daqing City,which is located in the Songnen Plain.It is a typical soda-type saline soil area and is a high-latitude deep seasonal frozen soil area.The development of unfavorable geological phenomena in the study area,especially the phenomenon of frost heaving,melting and sinking and salt swelling,causing corrosion damage to various buildings caused by saline soil,seriously affecting the durability and safety of various buildings.In this paper,0-40 cm saline soil in the study area was selected as the research object,and the basic physicochemical properties of the saline soil,direct shear test,freeze-thaw cycle test and triaxial shear test were carried out to study the strength characteristics and influence mechanism of saline soil.Detailed analysis.The research content of this paper is as follows:(1)Through field investigation and analysis of domestic and foreign research status,the classification and distribution of saline soil and the occurrence environment of soda saline soil in the study area are discussed,and the climatic conditions,precipitation and precipitation of Duerbert County in Daqing are discussed.The relationship between the evaporation amount,the salt migration route of the saline soil,the change of the speed of soil salinization,and the design and construction of the project bring harm.(2)Comprehensively study the basic physical and chemical characteristics of saline soil in the region,including the determination of physical indexes such as water content,particle grading and liquid plastic limit,and the determination of the chemical properties of the soluble salt content and the composition anion and cation content;To study the strength characteristics of soda-type saline soil,and analyze the variation of shear strength with salt content by direct shear test.(3)Preparation of four different saline contents(0.6%,1.1%,1.6%,2.1%)of reclaimed saline soil,and the triaxial consolidation drainage shear test and frost heaving test under freeze-thaw cycles Determine the shear strength of saline soil under different freezing and thawing cycles,different confining pressures,and the frost heaving and sedimentation amount of saline soil.