Study On Collapsibility,Physical Index And Structure Of Loess In Luliang Area

Collapsible loess is a kind of soil with special properties,and it will settle to a certain extent when it encounters water.In today’s society,the country is developing rapidly,comprehensively carrying out urban planning and urban construction,and creating a new look for the country.Various projects such as high-rise buildings and hydropower stations have sprung up.The collapsibility of loess has also become an important factor affecting the safety of these projects.Then,it becomes very important to understand the cause of the collapsing of the loess and avoid or eliminate the collapsing of the foundation or the harm caused by a small amount of collapsing.This article is a project based on geotechnical testing and comprehensive research in the Luliang Mountain area.Sampling points are arranged on the east and west sides of the Luliang Mountains from the south to the north,5 sampling points are arranged on the west side,and 4 sampling points are arranged on the east side.Sampling of loess.First,routine tests,collapsible and particle tests are carried out to obtain density,void ratio,clay content and collapsible coefficient in the laboratory,Then analyze the distribution of clay content,density,porosity and collapsible coefficient of the loess in the east and west sides of the Lvliang Mountains in the vertical and horizontal directions.Then combine the collapsible coefficient with the clay content,pore ratio and density,analyze the correlation between them,make their scatter plots,and analyze the changes of these loess physical indicators and collapsible coefficient.At the same time,a multiple linear regression method was used to establish a quantitative analysis model between the loess collapsibility coefficient and these physical indicators.Secondly,combining the collapsibility of loess with physical indicators,the correlation between the clay particle content,void ratio,density and collapsibility coefficient of loess was analyzed,and their scatter plots were made.The change law of the coefficient is analyzed.At the same time,using the method of multiple linear regression,we can creative a formula with influence factor to analy collapsibility.Then use mathematical methods to determine the degree of influence of clay content,void ratio,and density on the collapsibility coefficient,and see which physical index on the east and west sides of the Luliang Mountains has the greatest influence on the collapsibility coefficient.Finally,through the confined compression test and collapsible test,the undisturbed soil samples and the remodeled soil samples with different water content were arranged to study the structure of the loess in Luliang area.The study found that: due to the combined action of water and force,when the pressure is small and the water entering the pores is relatively small,the interior of the loess is stable and the structure is strong;while the water content in the loess increases and the pressure increases,the internal structure is destroyed,Then its structure becomes weak.The structure of the loess is the main cause of the collapsing of the loess.When the loess is structurally large,it is affected by moisture,and the settlement deformation of the collapsing is also large,which is reflected in the increase of the collapsing coefficient.