Numerical Analysis Of Influence Of Aquifuge On Temperature And Moisture Field In Subgrade Of Seasonal Frozen Region

With the construction and operation of highway in seasonal frozen region,the problem of stability for seasonal frozen subgrade under freeze-thaw cycle effect has gradually attracted people's attention.For seasonal frozen area,keeping the stability of humidity is an important way to guarantee the stability of frozen roadbed and improve the durability of roadbed.To solve the problems in seasonal frozen zone,“double isolation layer technology” of seasonal frozen subgrade was firstly proposed and adopted in the background engineering entity.Setting double isolation layer is mainly aimed at isolating the capillary water and minimizing the amount of ice in road bed.And it can isolate the seepage from the top surface to achieve long-term stability.Based on this mechanism,the material properties,lacation and its effect on temperature and misture field of subgrade are researched by numerical simulation in this thesis.Firstly,we thesis carried out subgrade soil's basic experiments of supporting projects firstly,and analyzed the particle composition,chemical composition,physical and mechanical properties of soil samples,and then defined its frozen classification according to foreign and domestic research.Subsequently,we collected local meteorological data and establishd subgrade temperature field finite element model of seasonal frozen zone using ABAQUS finite element software to analyze the seasonal variation of temperature,to estimate ice gather position,and to provide the evidence for setting double isolation layer.Finally,we ran the numerical model using ABAQUS finite element software,which can evaluate the effects of aquifuges with variant locations.In order to guide the actual construction of double isolation layer,the thesis also noted some quality control measures and some problems that should be considered during subgrade design and construction.