Emulation Of Widening Embankment And Asphalt Pavement Structure Under Traffic Loads

Broaden pavement roadbed uneven settlement caused structural damage has become oneof the issues requiring attention in Expressway Extension Project, For the handling of theproblems in this area will affect the safety and quality of road performance. At present，Thereis a lot of research at home and abroad for the problem of uneven settlement，But the impactstudy is less，which according to the traffic load of widening embankment settlement and theasphalt pavement structure.Based on the Hong Kong and Macao highway expansion project of Beijing-Shijiazhuangsection as the background, First of all, the existing embankment settlement calculationmethods are analyzed and compared; then using the finite element simulation, comparativeanalysis of the top of the embankments settlement with and without traffic load cases indifferent height. At last, the simulation analyzes asphalt pavement structure action of force insome embankment settlement form based on traffic load.The results show that: traffic load in widening the road settlement is a great influence,especially for the low embankment；When the embankment reaches a height of up to10meters, the traffic load on the sub grade settlement affects less than5percent；Traffic load istreated as cyclic loading, and the embankment gradually produces cumulative settlement,however, the deformation growth rate with load increase in the number gradually decreases；Influence degree of vehicle overload along with the increase of the embankment heightsmaller, axle load25kn (vehicle weight2.5t) can be neglected; Considering time effectcaused by uneven settlement of additional stress in broadening the pavement structuredistribution is related with surface materials relaxation effect, the failure forms may be facingsurface first to fracture strength, also may base surface tension stress first to breakdownstrength and failure; In the FWD load, under the action of surface tension stress variation lawwith time and traffic load variation law with time are similar, the calculated value in the trafficload compared with the action of static loads is smaller, so use static load as design criteriawill be more safety.High embankment of the road at the top of the stress relaxation faster, and more attention should be paid to low embankment is sub base bottom reverse bending stress influence, thehigher the temperature, the faster the stress relaxation, stress the more obvious changes.