Multi-objective Optimization Research On Road Collection And Distributing Network For Large Container Port

With the development of containerization,the scale of container ports expands continuously,the port throughput is increasing year by year.The construction of road system in container port has became one of the main factors which is the indemnification of the port service level.The traffic in port road system contains freight traffic flow derived from the random arrival of the container ship and increasing city traffic flow.So,it is inevitable for port road system to have some adverse characteristics,such as,mixed traffic flow,accident proneness,high congestion rate and so on,as the coupling influence of mixed traffic flow.However,due to the complex internal contradiction the mixed traffic flow conflicts in the road collection and distribution network,and the strong correlation between the selection of the port road and the throuthput,it is hard to use this method that planning the transportation function of the corresponding road section in the road network,and dividing the mixed traffic flow to improve the efficiency of freight collection and portation of road network.Thus,based on the analysis of the mechanism of frieght traffic generation in container port road network,and the traffic characteristics of the road collection and distribution network,this study combines the static traffic flow distribution theory and builds a multi-objective optimization model for highway collection and distribution network in container port area under the guidance of the multi-objective optimiazation theory.Firstly,the model takes the freight traffic flow as the research object,and takes the efficiency of the collection and distribution in the road network as well as its interference degree to the urban traffic as the optimization targets,uses the road function attribute as the solution variable to match the corresponding constrains under the actual conditions describing the internal conreadiction between the two optimization goals.Then,the function and principle of NSGA-II algorithm and improved Dial algorithm has been further analyzed to build a fusion algorithm which use NSGA-II algorithm as the core framework,and use Dial algorithm for the function of traffic flow allocation.The fusion algorithm is a solution to the multi-objective optimization problem in this paper,to get the optimal sub-network in the road collection and distribution network.Finally,taking a large container port area in the north as an example,the multi-objective optimization model proposed in this study is used to solve the pareto solution set of the optimal choice in the road network under the full-scale operation of the port area in the future.The research results show that the optimization model proposed in this paper can solve the path optimization problem under the multi-OD conditions in the actual port area.The mutual restraint relationship between the efficiency of freight traffic in the port area and the traffic interference degree to the city traffic has been proved.The network multi-objective optimization model proposed in this study can solve the problem of the collection and distribution channel selection in the planning and design stage of the port area,and provides theoretical support for the scientific and rational design collection and distribution system.