Study On Electroosmosis And Water Migration Law Of Unsaturated Loess

Water content is one of the important factors that affect the strength and stability of unsaturated loess.Reducing the water content of unsaturated loess is an effective method to strengthen the soil and improve the stability of foundation pits.Electroosmosis is an emerging foundation treatment method,which can quickly reduce the moisture content of the soil and accelerate the completion of the drainage consolidation process.At present,the research on electroosmosis at home and abroad is mainly aimed at soft soil saturated foundation,and there is still a lack of literature on unsaturated soil.Can electroosmosis cause water migration in unsaturated soil? What is the amount of water migration? How to determine the electroosmotic potential causing water migration? In this regard,this paper evaluates and analyzes the water migration phenomenon of unsaturated loess caused by electroosmosis under different initial conditions through one-dimensional electroosmosis test,and considers the actual project to carry out two-dimensional electroosmosis test to further improve the electroosmosis method in unsaturated soil Research.First,the mesh electrode,single column electrode and plate electrode were used to conduct the one-dimensional electroosmosis test of unsaturated loess.The comparison of the test results showed that the test results of the column electrode were consistent with the test results of the mesh electrode and the plate electrode.The columnar electrode can be used in the one-dimensional electroosmosis test,which also provides a basis for drilling and laying electrodes in the one-dimensional electroosmosis condition of the actual project.Based on the test results,the relationship between the water migration of unsaturated loess under the action of electroosmosis and the soil density,water content,electric potential,time and other factors is proved,and the calculation formula of the water migration under different electric potential and time is obtained through regression analysis.According to the measured current value and electric potential value,the soil resistance and interface resistance are calculated,and the relationship between unsaturated loess resistance and water content is obtained through regression.After that,the finite element calculation model of unsaturated loess water migration was further adopted,and a flow chart for back-calculating the water potential was given.Taking the one-dimensional test soil sample as the object,the water content distribution was calculated by formulating the water potential expression of the action of electric potential.Compared with the test results,the expression of water potential considering the effect of electric potential is initially given.The self-made two-dimensional electroosmosis test device reveals the evolution law of the moisture field and electric potential of unsaturated loess under the action of twodimensional electroosmosis through the two-dimensional experiment,and proves the water migration and soil moisture content of unsaturated loess under the action of twodimensional electroosmosis,Density,time,electrode form and other factors.The results show that: when the initial moisture content is the same,the greater the saturation of the test soil,the greater the decrease in the moisture content of the anode area after the test.When the saturation is the same,the smaller the dry density of the test soil,the greater the amount of water migration,and the effect of water migration The more obvious;the reduction value of the moisture content in the anode area when the center electrode is the anode is greater than that when the ring electrode is the anode,and the electroosmosis effect of the mesh electrode is better than that of the hexagonal electrode arrangement.