Analysis method of urban road network structure based on complex network

Based on urban road network, the feasibility and effectiveness of complex network theory application were analyzed.By using Dijkstra shortest path algorithm and Space L method, the initial topology network was built, and the characteristic index models of the degree of node, the degree of edge and the road impedance of node were set up.Under the premise of reflecting the reality of road network function, the initial topology network was optimized, and empirical analysis was carried out by using road traffic data in a central urban area.Analysis result shows that in the initial topology network, the average node degree is 2.850 0 and the standard deviation of node degree is 0.670 8.The average road impedance of node is 84.680 0 s and the standard deviation is 11.768 8 s.While in the optimal topology network, the average node degree is 38.750 0 and the standard deviation of node degree is 24.683 0.The average road impedance of nodes is 91.780 0 s and the standard deviation is 18.862 8 s.The average degree of east-west road section is 42.00, the average degree of north-south road section is 29.86, the average degree of internal section is 55.00, and the average degree of external road section is 28.33.In the optimal topology network, when the node with large degree is not stable, the road impedance of shortest path will increase in non-crowded state, and the road network will be paralyzed in crowded state.The node with higher degree is accord with the importance degree of intersection in real road network, and the difference of importance degree for intersection can be more reflected.