Research on Dynamic Stress of Low Embankment Considering the Influence of Pavement Structure
Relying on a highway in Nigeria,this paper studies the dynamic stress distribution of sand-gravel low embankment considering the pavement structure layer under the traffic loads.This paper firstly analyzes the influence of speed and axle loads on the dynamic stress of roadbed through field test.On this basis,a three-dimensional finite element model is established to analyze the influence of different roadbed heights,overload rates and different filling modulus on dynamic stress distribution.The field test results show that the faster the vehicle travels,the smaller the stress peak value,the heavier the vehicle weight,and the higher the internal dynamic stress of the roadbed.When the pavement is flat,the vehicle weight is the main factor affecting the dynamic stress of the subgrade and the vehicle speed has little effect.The numerical simulation results show that the internal dynamic stress of the subgrade is proportional to the height of the embankment,the overload rate and the modulus of the subgrade filler.The subgrade working area decreased from 1.92 m to 1.79 m,the overload rate increased from 0 to 125%,the subgrade working area depth increased from 1.77 m to 2.73 m,with an increase of 54.2%,and when the subgrade modulus increased from 80 MPa to 160 MPa,the subgrade working area decreased from 1.77 m to 1.58 m,which the rate of decrease is 10.7%.The test results show that overloading has the greatest influence on the dynamic stress.The conclusions of this paper provide a reference for the design of low embankment.
highway engineeringlow embankmentdynamic stresssubgrade working areanumerical simulation