The Spatiotemporal Analysis Of Urban Road Diseases And The Research Of Maintenance Decision Optimization

With the rapid urbanization and increased road mileage of our country,the roads disease is becoming more and more frequent,and the maintenance needs are increasing day by day.Our country invested a lot of fiscal funds for road maintenance engineering.But the history of road maintenance is very short in many cities,the decision of road maintenance was usually made by traditional method of using road engineering structure analysis.The maintenance decision-making level is not high that leads to the increasingly huge funding gap on the road maintenance.In this paper the characteristics of urban road diseases,including time,density and distribution,are spatiotemporally analyzed by GIS technology.Then,the occurrence rules of urban road diseases are concluded.which is of certain significance for the urban road preventive maintenance plan.Aiming at the problem of limited budget when conventional urban road maintenance decision-making was made,the decision-making optimization model with the greatest effect of limited budget maintenance was constructed,and the single-objective maintenance decision-making optimization model was solved by integer programming algorithm.For the multi-objective optimization of road maintenance decision-making,the minimum maintenance effect and maximum maintenance effect of budget are pursued.Build road maintenance decision optimization models with minimal maintenance costs and the highest maintenance costs.The optimization model of multi-target maintenance decision is solved by genetic algorithm.The results are as follows:(1)This paper was based on the road inspection data from 2016 to 2018 in Shushan District of Hefei city.The distribution of road diseases in the street area was obtained by GIS technology.Kernel Density Estimation(KDE)was used to conduct spatiotemporal analysis of road diseases,and the analysis results were presented visually in thematic map by combining with GIS technology.(2)In the case that the road management department has limited funds available(such as an annual budget of 10 million yuan),the single-objective maintenance optimization decision model was adopted to obtain the solution of the maximum value of the maintenance road PCI.The integer programming algorithm was used to solve the decision-making optimization model with the lowest cost of maintenance road disease and the PCI level reaching A level(90 points).The total value of PCI of repaired roads was 1547.79,and the corresponding cost of repairing roads was 9123600 yuan.The single objective road maintenance decision optimization scheme was made into the road maintenance thematic distribution map by GIS technology.(3)The minimum maintenance budget and maximum PCI value of all roads after maintenance are the two goals of maintenance decision optimization.A multi-objective optimization model with maximum effect and minimum cost is established,and the Pareto optimal solution is obtained by genetic algorithm.This paper takes the annual conservation decision of the study area as the actual demand,and obtains 70 optimization plans by applying the model to the decision of the road maintenance unit.In the solution set of the model,the repaired PCI value is 1502.73,the maintenance fund is the optimal solution of8026000 yuan,and the optimal solution of road maintenance decision is incorporated into the road maintenance topic distribution map by GIS technology,and it is visually presented.