Numerical Analysis Of Deformation Influence Factors Of Compaction Loess Subgrade

As we known the subgrade of compacted loess is widely used in the loess area.With the rapidly increasing of traffic mileages and carrying capacity of transportationabout highway and ordinary road, there raise many problems in the use of compactedloess subgrade, such as foundation subsidence, slope collapse, pavement frost heaveetc. Which have shortened the road service life. What’s more, there will be moreproblems in the compacted collapsible loess subgrade. However, the repair work notonly affects the normal use, but also causes a considerable economic losses andmaintenance costs. It is studied systematically in this paper that the deformation of thecompacted loess subgrade is effected by the dynamic load.The dynamic vehicle loads will cause deformation of subgrade in the long time,and the mechanization of vehicle loads are complicated. In this paper, we statisticsand analysis the characters of load through the field experimentation, and take mainfactors into consideration, then get a curve of dynamic load time.Combined with the characteristics of compacted loess, a reasonable materialmodel is given. And the parameters of model are obtained. According to the actualsituation, a reasonable geometry model is discussed in detail. Based on the research,the finite element numerical analysis of dynamic loads on dynamic response loesscompaction subgrade calculated and additional dynamic stress and strain in thecompacted loess roadbed displacement distribution law is obtained.This paper focused on the basis of the numerous factors influencing deformationof compacted loess subgrade, the subgrade under different conditions is analyzed.Some useful conclusions are obtained. The degree of compaction is the mostimportant index to judge the trend of compacted loess subgrade, and the verticaldisplacement of different degrees of compaction loess roadbed can be expressedas y7.4362x215.515x8.604. This can be used to estimate the change in thevertical displacement under different compaction degree. Change in the structure ofloess to water is very sensitive, by analyzing the relationship between a bit shift andmoisture content for: y40.158x28.6119x0.8684Effect of the water content is theprimary cause of many engineering problems. The dynamic load is one of the mainreasons influencing highway subgrade deformation, the relationship between verticaldisplacement and load amplitude for:y0.1346e0.0021x.The relationship between thefrequency and load: y0.00482(lgx)30.4360(lgx)21.3266lgx0.6364.In summary, this paper obtained the compacted loess subgrade strain in differentdegrees of compaction, water content, pavement structure and loading condition anddeformation law quantitatively. It would provide some reference basis for the highwayconstruction in Loess area.