Analysis Of The Effect Of Subgrade Frostinsulation Board In The Seasonal Frozen Soil Area

With the rapid development of the national economy, people has increased the building effort of theinfrastructure. It is inevitable putting more effort in terms of road works while conducting the infrastructure.However, the frozen soil area is widely distributed in our country, the influence of freeze-thaw damage ofroad engineering cannot be ignored. So it is necessary to strengthen the research on the direction ofpreventing subgrade heaving to guarantee the normal operation of the road. The paper simply introduces avariety of ways to protect the frozen soil subgrade, and analyzed the principle of the heat preservationmethod of protecting permafrost roadbed, its influencing factors and the permafrost subgrade frost heavingand feature. It iskNow that the insulation board in the roadbed can effectively prevent subgrade frostheaving, compared to other methods of protect permafrost subgrade, it is very economic and applicable. Onthe basis of analysis of a large number of engineering data, through dimensional analysis, and with the aidof finite element analysis software ANSYS to carry out the following research:(1)Taking the practical engineering as the example, using ANSYS software to simulate thetemperature field of the embankment about the ordinary roadbed and the insulation board. After thecomparative analysis, found that the insulation board and its surrounding soil subgrade temperature fieldchanged which0℃frozen line enhanced greatly.(2)Analysing freezing the process of the subgrade, on the basis of previous studies, considering themain factors affecting the laying thickness of insulation board, the empirical formula of subgrade insulationboard reasonable thickness in seasonal frozen area is obtained by the method of dimensional analysis.Choosing practical engineering as an example, analysing the affect results in different thicknesses ofinsulation board after laying the roadbed in permafrost roadbed. It was found that the0℃freezing line isusually rise to the surface of the insulation board, and the thicker of the insulation board, the betterresistance to frost heave. When the subgrade height is3.0m, the reasonable thickness is0.1m.(3)Analysing the freezing process of the embankment, on the basis of previous studies, considering themain factors affecting the depth of buried insulation board, thinking over the subgrade insulation boardreasonable depth empirical formula in seasonal frozen area by the method of dimensional analysis. Pickingpractical engineering as an example, analysing the affect results in different locations in the permafrostroadbed laying insulation board and the freezing line is usually found0℃to rises to the surface of theinsulation board. Insulation board nearer the roadbed surface, the effect is more anti-frost heaving well.When the embankment height is3.0m, the reasonable burying depth is80cm under the pavement.