Study On Performance Evaluation And Preventive Maintenance Countermeasures Of Expressway Asphalt Pavement

Preventive maintenance is the most effective way to maintain high pavement performance under limited funds,at present,China highway preventive maintenance system is not perfect,especially in today’s insufficient maintenance funds,how to balance between limited funds and a large number of pavement maintenance is the main problem at present.Based on the research of Daguang high-speed(Hengda section),through the analysis of the maintenance data and test reports,the thesis adopts Abaqus finite element model,entropy-ahp method and grey BP neural network model,weighted Grey target decision model,this thesis makes a comprehensive study on the current pavement condition,dynamic response of pavement,weight combination of pavement quality index,prediction of pavement performance data and selection of maintenance section,and made the corresponding research results.(1)This thesis introduces the basic condition of Daiko Advertising Expressway,then points out several common damage forms of asphalt pavement and analyzes the reasons.The pavement condition of the main line of Daiko Advertising Expressway(Hengda section)was evaluated by highway technical condition,pavement technical condition and pavement damage.(2)A model of asphalt pavement under moving loads was established using finite element software ABAQUS,and the dynamic response laws of maximum tensile compressive stress and shear stress in each layer of the pavement were analyzed.And the influence of changes in external parameters of the pavement model on the dynamic response of the pavement was explored,and it was found that factors such as driving speed and axle load have a significant impact on the performance of asphalt pavement.(3)By using the method of entropy-analytic hierarchy process(AHP),the weight of each index of pavement technical condition index is redistributed under the premise of considering the subjective and objective factors,the actual weight of Daguang high speed is determined and re-calibrated.(4)Based on the data of pavement performance in recent years,the short-term prediction is carried out by using the Grey BP neural network model,it is more accurate than GM(1,1)model and has achieved good results.(5)The maintenance standard of pavement performance is determined,then the priority of diseased road maintenance is sorted by using the weighted grey target decision model,a variety of preventive maintenance measures are put forward,and the decision tree is established.