Research On Influence Of Salinization Concerning About Engineering Properties Of Loess And Its Improvement

Loess is a Quaternary yellow silt deposit widely distributed in the northwestern part of China.Due to the lack of rainfall in the western region,the amount of evaporation is greater than the rainfall,and the rough form of irrigation adds to the degree of salinization of the soil to some extent.Along with the development of China's western region and the strategy of the Belt and Road Initiative,the infrastructure construction in the western region is becoming more and more perfect,and the development is changing with each passing day.However,due to the complex and varied topography of the western region,it is difficult for engineering and geological personnel to construct in the western region.Avoid encountering a variety of geological problems,the most prominent of which is the construction of the saline soil area.Therefore,it is very necessary to conduct in-depth research on the engineering properties of loess during salinization.In this paper,Yangling loess was used as the research object.By adding 0.1%,0.3%,0.5%,1.0%,2.0%(mass fraction)of chloride salt in Yangling loess,the water content of13%,16%and 19%was set.And four dry densities of 1.38g/cm~3,1.48g/cm~3,1.58g/cm~3,and 1.68g/cm~3,through specific gravity test,particle analysis test,boundary moisture content test,compaction test,Zeta potential test,pH test,direct Shear test,compression test,penetration test,collapsibility test etc,to explore the effects of salt content,water content and dry density on the physical and chemical properties and engineering properties of different degrees of salinized loess.At the same time,the engineering properties of the saline soil were improved by adding different amounts of desulfurized gypsum(the main component is calcium sulfate).The result turns out that:(1)With the gradual accumulation of salt content,the relative density of soil particles gradually decreases;the particle analysis test shows that the soil particles will agglomerate with the increase of salt content;the liquid plastic limit shows a trend of increasing firstand then decreasing;soil The maximum dry density is gradually increased,and the optimal water content of the soil is gradually reduced;the pH of the soil shows a trend ofdecreasing first and then increasing;the potential of the zeta potential first increases and then gradually decreases.(2)With the increase of salt content,the permeability coefficient of soil graduallydecreases;the cohesion force generally increases first and then decreases.At 13%and 16%moisture content,the internal friction angle is 30°.There is a fluctuation between 40°,but it is W-shaped when the water content is high.With the increase of salt content,In high water content the compressibility coefficient of saline soil increased and then decreased.The collapsibility coefficient of saline soil increased with the increase of salt content,and decreased with the increase of dry density.(3)With the increase of desulfurization gypsum content,the permeability and cohesion of soil generally show a trend of increasing,but the influence on the permeability coefficient is limited.The compression coefficient decreases first,then increases with the increase ofdesulfurization gypsum.The amount of desulfurization gypsum incorporation has no obvious effect on the internal friction angle,and has little effect on the collapsibility coefficient...