Assessment of Highway Network Development Level Of Urban Agglomeration in the Central Plain of China

Highway network,providing express access between cities is critical to the integration of the urban agglomeration of the central plain of China.Based on the shortest path matrix of 20 cities,we have quantitatively evaluated the highway network development level of the region by the accessibility index,extension index,conglomeration index,and etc.The result shows that in the space structure the highway network development level is a core-margin model.The cities with higher accessibility indexes gather around Zhengzhou City,while those with lower ones distribute in the margin.The order among conglomeration index is accordant to that of accessibility index.So the accessibility of cities in margin should be improved,and the highway network in landscape orientation from south to north of the region should be strengthened.