Study On The Theory And Method Of Road Network Optimization Based On Four Factors

With the great development of society and economy, transportation demand is increasingrapidly, which requires the higher applicability of road network. At the same time, due to theinsufficient consideration of transportation demand, the construction of current network is outof equilibrium with problems of traffic congestion and unreasonable smooth, which restrainsthe functioning of network. In this instance, study the coordination of new-built roads and thecurrent network is of great significance to enhance the network system and keep it adapt tothe development of society and economy, via developing the potential of current network andplaying the advantages of new-build ones.To the subject of road network optimization, take the four factors of construction cost,the opportunity cost of land, transportation cost and the efficiency of road as decisionvariables, the paper builds a comprehensive assessment model based on the four factors fromthe point of social and economic development. And then, on the four factors analysis oftri-node structure, the paper proposes an optimization method of network by adding virtualnode, and the location of ideal virtual node is discussed, it is affected by the trafficdistribution, the shape of the tri-node structure, etc. it’s almost impossible to get its analyticalsolution, hence, a network optimization model based on four factors is built, and thenumerical solution of the ideal virtual node by PSO is proposed.At the end, empirical study is taken by the example of Middle-Western Guangdong, anda comprehensive optimization plan is proposed to solve the current problems. The conclusionindicates that: the comprehensive optimization plan functions very well to solve the problemsof traffic congestion and unreasoning smooth, after its implementation, the efficiency of roadincreased greatly, and the network functions improved apparently.