Research On Maintenance Indices' Threshold Of Shaanxi Common Trunk Highway Asphalt Pavement

With the development of the road transportion,China's highway mileage has been to meet the need of economic development mostly.In recent years,the highway in Shaanxi Province has also entered a area of cyclical maintenance.The maintenance measures decision-making approach still rely on experience to judge,due to the data accumulation of road maintenance history is still relatively small,the research on pavement performance decay prediction also in the initial stage,the criterion for judgement of indices' threshold of preventive maintenance,intermediate maintenance and heavy maintenance is still more subjective.The range of indices' threshold about pavement maintenance decision-making is broad,does not take into account the regional climate,traffic,pavement structure and other factors,the actual application depends on the qualitative understanding and the experience of Engineers,so in decision-making often Waste of maintenance funds and other phenomena.The paper collected the data of the common trunk highway asphalt pavement over the years and takes the maintenance design plan.By summarized it,select the representative roads which can represent the characteristics of the pavement in each region respectively.Analyze the distresses of the pavement,find out the main distress and analyze the causes.Based on the collected trunk highway maintenance data of Shaanxi province,the appropriate pavement performance decay model was selected to establish a forecasting process and parameter correction method of pavement performance decay law in line with the common trunk road maintenance in Shaanxi Province.Based on the pavement performance decay curve,the indices' threshold of preventive maintenance is determined.According to the relationship between Pavement Structure Strength Index(PSSI)and Pavement Surface Condition Index(PCI)and Riding Quality Index(RQI)are analyzed,and the thresholdes' ranges of maintenance indices are determined based on the existing pavement maintenance indices' standard.Statistical analysis was carried out on five representative methods(sort percentile method,linear regression method,normal distribution change method,square root method and cubic root method)for indices' thresholdes of preventive maintenance,intermediate maintenance and heavy maintenance.By the method of the best stability of the five methods to calculate the results as a preventive maintenance indices' threshold,and then refer to the threshold on above definition of the conservation,combined with the specific circumstances of conservation measures,comprehensive analysis.Finally,determine the final indices' threshold of preventive maintenance,intermediate maintenance and heavy maintenance.