The Study On The Evaluation And Prediction And Decision Of Expressway Asphalt Pavement Performance For Gansu Province

Under the strong support of the provincial Party committee and the provincial government for the transportation construction in Gansu Province.The road construction has achieved remarkable results in Gansu Province.The rapid development of highway construction has effectively relieved the tension in transportation.At the same time,with the increase of traffic volume.Rutting,cracking and other diseases of the road have appeared on some sections of the highway,which seriously threaten traffic safety and reduce the service level of highway.Traditionally relying experience and semi-empirical conservation decisions resulted in serious wastage of conservation funds and increased road damage.Therefore,to effectively reduce the wastage of maintenance funds and improve the performance of the pavement,an efficient highway asphalt pavement maintenance decision system needs to be established.Based on the highway asphalt pavement in Gansu Province,this paper studied the performance evaluation,prediction and decision-making techniques of highway asphalt pavement.The main research results as follows:Combined with the general conditions of highway construction in Gansu Province and the existing zoning studies,the highway network in Gansu Province was divided into four sub-zones.Statistical analysis was performed on the types of leading damage of the asphalt pavement in the four sub-district highways.Statistical analysis showed that: The type of leading damage in zone I was repair and rutting;the dominant damage type in Area II was repair,rutting and cracking;the dominant damage type in Area III was transverse cracks;the dominant damage type in Area IV was longitudinal cracksThe main component-cluster analysis method was used to study the segmentation of the maintenance section.As for the defect of PCI as an indicator for the segmentation of maintenance sections,the paper selected 10 diseases of asphalt pavement,rutting damage index(RDI),driving quality index(RQI),and skid resistance index(SRI)as indicators for dividing road sections.The main component-cluster analysis method is used to divide the maintenance section.The results show that the principal component-clustering method can classify the road which has the same road conditions into one category sections,and there is a large difference between the different categories.Using the principal component analysis method to reduce the dimension of the road condition will not affect the road section segmentation and the evaluation of pavement condition grade.In addition,the redundancy of information can be minimized,and the road segmentation result is more scientific and reasonable.The method of evaluating the performance of highway asphalt pavement based on the grey TOPSIS method was studied.the performance evaluation index system and performance evaluation standard of highway asphalt pavement in Gansu Province were established,and then the weights of the sub-indexes of the road performance for the four road network sections in Gansu Province was determined by game method.Based on that,the gray TOPSIS method was used to evaluate the pavement performance.The results show that the comprehensive weights determined by the game method are comprehensive reflection of subjective weight and objective weight.It can not only fully consider the subjective weight of the experts(ie,the weights in the specification),but also fully reflect the dominant damage types of the road sections.The comprehensive weights are scientific and reasonable,which helps to improve the accuracy of gray-TOPSIS method for comprehensive evaluation of pavement performance;the evaluation result that based on the gray TOPSIS method is more accurate than the comprehensive evaluation results in the specification,and it is more conducive to the decision-making guidance for maintenance.Road performance deterioration model for Gansu Province was established.Integrating with highway condition investigation and taking into account the differences in climatic factors and maintenance levels in different regions,the road network partition in Gansu Province was used as the unit,selecting a typical road section in each area established a decay model for the performance of asphalt pavement.PCI and RDI are determinied as predictions;the road deterioration model is established for each region.Pavement detection data 0f 2017 is compared with the forecast data.The results show that the prediction errors of the PCI and RDI forecast models is average 4%,and the prediction results are more reliable.The decision method of asphalt pavement maintenance for Gansu expressway is studied.According to the highway condition and the current situation of maintenance and management of Gansu province,the expectation level of highway asphalt pavement maintenance in Gansu province is determined.Through the investigation of commonly used large and medium repairs and preventive maintenance measures for expressway asphalt pavement in Gansu Province,combined with the applicable conditions of various types of conservation measures,the status of maintenance funds and the combination of road surface conditions,Decision tree of the selection of highway asphalt pavement maintenance measures in Gansu Province was established.Based on the benefit-cost analysis method,the optimal timing of asphalt pavement maintenance in Gansu Province was determined.The optimal conservation time and maintenance costs were determined for the typical sections in Zone I and Zone IV.Based on the research of performance evaluation,prediction and maintenance decision in this paper,a decision-making system of highway maintenance for Gansu Province was developed.The system are realized the maintenance's decision of any expressway in Gansu Province,and finally generated a maintained decision's report for the designated road section,which can be used by the conservation management department for maintenance decision-making.