Study On Erosion Mechanism Of Dispersive Clay In Zhenlai,Jilin Province

In recent years,with the rapid development of the society,more and more land is needed,especially in infrastructure,public and civil buildings and so on.Therefore,it is very important to study and improve the characteristics of special soil.Recently,the dispersive soil in geotechnical engineering is one type of the most important soil.The ability of soil to resist water erosion is poor.It is a threat to the safety and stability of water conservancy projects and road projects.Article combines the National Natural Science Foundation of China “study on the mechanism and effect of engineering geological environment disaster evolution system under HTSM multi field coupling about soil salinization in arid and cold regions”.Article takes the dispersive clay in the Jilin Zhenlai as the research object.The basic properties of the soil samples at different depths in Zhenlai area and the dispersive identification test were carried out,in order to study the relationship between the basic physical and chemical properties and dispersion of soil samples in vertical section.According to the situation of the three kinds of laboratory identification test of dispersive clay,namely pinhole test,double hydrometer test and crumb test and taking into account the characteristics of dispersive soil,it is easy to collapse after the water,and is easily taken away by water.The shear strength,erosion resistance and physical and chemical properties of the soil were changed.Therefore,the laboratory small slope mold and rainfall device were utilized.A laboratory physical simulation erosion test was carried out on the dispersive soil in the study area of Jilin,Zhenlai.The erosion failure law and its main influencing factors of the dispersed soil slope with different salt content,different initial water content,different compaction degree and different slope were studied.The conclusions are as follows:(1)The results of the comprehensive evaluation of the study area in Jilin,Zhenlai Province,the soil samples with the depth of 10~40cm and the soil samples with the depth of 60 cm are dispersive soil.The soil sample with depth of 80 cm is non dispersive soil.The soluble salt content of the soil samples was higher.The soluble salt content of the soil sample with depth of 10~40cm and the depth of 60 cm was higher than that of the soil sample with depth of 80 cm.The distribution of soil samples in vertical profile was similar to that of soluble salt content.(2)The whole evolution process of erosion in the slope of the dispersed soil slope is divided into three stages: raindrop splash erosion,water dispersion and gully erosion.In the first stage,the raindrop erosion,raindrops hit the surface soil.The fine particles on the surface of the slope were splashed by rain drops,which were scattered,broken and scattered everywhere.Fine particles second pha se slope surface water after decomposed into primary clay particles.In the second stage,fine particle on the surface with water after decomposing into primary clay particles.The soluble salt in the soil is gradually dissolved in water.The basic physical and chemical properties of soil changed,and the strength parameters were affected.Some soil particles lose their stability.Erosion pits begin to form.In the third stage,along with the rainfall,the slope runoff increased significantly.The shallow gully is formed,and the shape of the slope is severely damaged by widening and deepening,eventually leading to complete destruction of the slope.(3)According to the simulated dispersion erosion test,we discuss the various factors affecting the initial water content,salt content,degree of compaction and the slope of the dispersion of soil scouring.The erosion mechanism and dispersion characteristics of dispersive soil were studied.It provides important theoretical guidance for the slope erosion and the protection of the water conservancy project in Jilin province.(4)Other factors also affect the dispersion of soil.The organic matter in soil is the cementing agent.The higher the content of organic matter,the stronger the agglomeration of soil particles and it makes the dispersion of soil samples weaker.Clay has fine grain and high surface area characteristics.There are adhesive forces between clay.The clay content directly affects soil permeability,thereby affecting the dispersion of erosion damage.