Deformation Stability Of Subgrade Under Longterm Heavey Loading In Seasonal Frozen Regions

Numerous highways are constructed in frozen regions of China,has been subjected to freezing environment and the impact of the dynamic load generated by the heavy loading vehicle,bearing capacity and deformation stability of the Subgrade are deteriorated sustained. At present, the seasonal frozen regions, think of the effect of freezing and heavy loading,analysis and research on the deformation stability of subgrade is still insufficient.This problem has always restricted the use function of highway subgrade,It also affects the traffic safety and the development of regional national economy. In view of this, this paper is based on the Qigihar Nenjiang highway K46+732 field subgrade section, the main clue are the heavy truck load and freeze-thaw cycle, by ABAQUS finite element analysis software of finite element analysis, using numerical simulation method, study on the temperature field of highway subgrade in seasonal frozen soil area, and study on dynamic response and permanent deformation of Subgrade under cyclic loading in the seasonal frozen soil area, the main research contents are as follows:(1)Set in the field of subgrade section, for field climate conditions, a three dimensional finite element analysis model of highway subgrade in seasonal frozen soil area is established; The temperature field of subgrade is calculated, the temperature variation law of the top of the subgrade, the middle layer of the subgrade the bottom of the subgrade and the natural basement layer are analyzed.(2)Based on Vload program, the dynamic load simulation of heavy load vehicle is realized, the finite element model of dynamic response of highway subgrade under heavy truck loads in seasonal frozen soil area is established; the dynamic stress amplitude of each layer is calculated, And analyzes the dynamic response variation of subgrade in different car axle, driving speed, depth, and freeze-thaw state.(3)Based on the analysis of subgrade soil permanent deformation model, introduced existing soil accumulated permanent strain model, use layered sum calculation method,establish of a calculation method of subgrade permanent deformation under long-term heavy load in frozen area road; it analyzes its variation with load times, And to compare the impact of subgrade permanent deformation in different car axle, forming velocity, freeze-thaw state.