The Optimal Timing Of Preventive Maintenance Of Highway Asphalt Pavements

Now, the premature damage of asphalt pavement in expressway is serious. So, the preventive maintenance has become the main point of asphalt pavement maintenance in expressway. Preventive maintenance prevents troubles before they happened, makes the road surface keep fairly good function in the longtime. So, preventive maintenance is particularly important at this time. Study and apply to preventive maintenance has great importance for curing to our country highway asphalt pavements.The dissertation began from the the concept and the significance of preventive maintenance .It put forward the necessary of researching the optimal timing of maintenance and the key issues.Based individual evaluate indexes of asphalt pavement performance and the requirements of asphalt pavement maintenance, the paper added the evaluate of index- rut and advanced the evaluate indexes system of highway asphalt pavements. It also put forward the weighted geometric mean to calculate the pavement performance evaluate indexes PQI, at the same time ,the method of the main and the impersonality conjunct was applied to make the weight of individual evaluate indexes of pavement performance.For the reason of lacking historic performance data, the GM (1,1) was chosen as the prediction model which is based on the least-squares theory.The paper analyzed several methods in world and introduced the DEA (Data Envelopment Analysis) to confirm the optimal timing of preventive maintenance.It set up the evaluation model in data envelopment analysis based on fictitious DMU and confirmed the inputs indexes(daily maintenance costs,pavement maintenance costs )and the output indexes (the maintenance benefit area of evaluate indexes,the life changing of pavement,remnant value).Using the model of DEA, the paper calculated several different decision-making cells of preventive maintenance time, and confirmed the optimal timing of preventive maintenance.