The Influence Of The Highway To The Evolution Of Urban Spatial Form Of Small Cities Along Expressway

Under the background of rapid urbanization, urban spatial form has been subject to drastic evolution. The expressway which constitutes an important part of modern integrated transport network has produced significant impact on the evolution of spatial form for the small cities along the line with its huge traffic and economic advantages. Therefore, it is of important and practical significance to study the evolution of urban spatial form under the influence of expressway. Taking five county-level cities under the jurisdiction of Weifang as the examples, this paper combines quantitative research with qualitative research, and analyzes the influence of expressway on the evolution of urban space from multiple perspectives.First of all, relevant researches at home and abroad are reviewed, on which relevant theories are combed to be as the theoretical basis for research on the evolution of urban spatial form. Next, anisotropy for the spatial expansion of case cities are analyzed by virtue of equal fan analysis method, and the influence of expressway on urban spatial expansion is explored from the dominant direction and scale of urban spatial expansion. Then, land analysis is conducted for increment regions along the dominant direction of urban spatial expansion, in order to determine the dominant functions of study area. Furthermore, functional composition of small cities within the spatial expansion region in the direction of expressway is analyzed, and further study on the spatial distribution characteristics of main functions in the region is conducted combining with the present urban situation. what’s, the concept of expressway connecting line is defined; types of spatial aggregation form for regions along the expressway connecting line are analyzed combining with the case cities, and advantages and disadvantages of various types of aggregation form are reviewed. Finally, evolution methods for urban spatial form under the influence of expressway are explored.Based on the study, conclusions below are reached:(1) during the period of rapid urban development, dominant direction of spatial expansion for small cities along expressway points to the expressway generally, and the scale of urban spatial expansion is relatively large in the direction of expressway. (2) The region subject to urban spatial expansion in the direction of expressway generally dominates industrial land. The development model of the region is usually divided into two kinds. One is the scale region subject to spontaneous formation under the attraction of traffic lines; another one is the industrial park or the economic and technological development zone developed and constructed under the guidance of planning and policies. (3) The type of aggregation form for regional space of expressway connecting line is divided into three kinds:one is the banded spatial form aggregated along both sides of the expressway connecting line; another one is the extensional spatial form along the expressway connecting line of main urban area; the last one is the enclave spatial form along the expressway connecting line. On this basis, evolution methods of urban spatial form under the influence of expressway are discussed, and the evolution methods of urban spatial form for five case cities are analyzed:Qingzhou belongs to banded development type; Gaomi and Changyi belong to shape expansion type; Shouguang and Chucheng belong to enclave development type.