Study On Influencing Factors Of Rainfall Infiltration Law Of Frozen Soil Subgrade Slope

In recent years,with the deepening of the strategy of revitalizing the northeast and western development,the transportation network construction and infrastructure construction in the seasonally frozen soil areas have been greatly developed,and more and more major transportation lines will be built in seasonal frozen soil areas.However,the annual average temperature in the frozen soil regions is on the rise,and the annual rainfall is gradually increasing.The occurrence of the instability of the frozen soil subgrade slope due to rainfall infiltration is increasing.Rainfall will cause changes in the physical characteristics and hydrothermal conditions of the surface soil.Rainwater infiltration leads to a decrease in soil matrix suction and a decrease in shear strength,which affects the stress field.At the same time,a large amount of heat is introduced to melt the ice crystals in the frozen soil.The amount of water increases,affecting the temperature field and the water field.For frozen soil with high ice content,rainfall will cause the change of negative pore water pressure to be more severe,which will cause the slope to be destroyed.Therefore,it is necessary to study the law of rainfall infiltration of frozen soil roadbed slope and the variation of water and heat in the soil.In this paper,the subgrade slope in seasonal frozen soil area is taken as the research object.The changes of water content,temperature and earth pressure of frozen soil slope under different rainfall,initial water content and slope ratio are studied.The data obtained are processed to summarize the rainfall infiltration laws of the frozen soil slope.Then the SEEP/W,TEMP/W,SIGMA/W modules in GeoStudio were used to simulate the water field,temperature field and stress field during the test,to further verify the reliability of the test results.The applicability of rainfall infiltration law of frozen soil slope at different depths is analyzed and summarized.It provides a theoretical basis for the study of seasonal frozen soil subgrade slopes under rainfall conditions.