Method Of Road Optimization In Small Cities

Some major traffic characteristics of small cities,such as the small scale of general situation,close contact with adjacent areas and the great impact of the development zones on urban traffic,are less considered in the classical road network optimization methods.For small cities,there is room for further improvement of the classical road network optimization methods.According to the characteristics of small cities,this paper focuses on the initial road network layout and inspection method and reasonable determination method of zone number.Combining these methods with other parts of classical theory,a road network optimization method suitable for small cities is formed.Firstly,this paper systematically summarizes and analyzes the related characteristics of city road network and zone.In view of the city road network,3 aspects are summarized and analyzed mainly from the characteristics of the road network,the planning principle and the influencing factors of the layout.In view of the zone,3 aspects are summarized and analyzed mainly from the division purpose,characteristics and division principle.Secondly,based on the characteristics of small cities,which are small in scale and close to the surrounding areas,this paper puts forward an initial road network layout and inspection method suitable for small cities.It is mainly aimed at the land area demand forecast of non-motor vehicle and vehicle roadway,which is optimized based on the classical method.According to the land area demand forecast of non-motorized vehicle roadway,it is subdivided into three kinds: between the city area and the city area,between the city area and the development zone,between the city area and the periphery,and subtracts the demand of the latter two kinds beyond the planned area.For motor vehicle,it is also divided into the same three types,and subtracts the demand of the latter two kinds beyond the planned area.The other parts of the initial road network layout and inspection method are optimized in detail.By combining the above research,the initial road network layout and inspection method is formed.Then,this paper aims at the actual situation that the traffic assignment results in small cities are not ideal because of the number of zone.The number of the zone is obtained by using the classical zone division method.A reasonable determination method of zone number in small cities is put forward.By analyzing the relationship between the number of zone and the precision of traffic assignment results,it is concluded that with the increase of the zone number,the accuracy of traffic assignment results will also be improved.According to the general common sense,it is suggested that the zone number in small cities should be more than 60 by setting the average saturation error of each section within 0.2 as standard.The saturation of each section is obtained after traffic assignment.The data which is about more reasonable zone number and population quantity is analyzed by using regression analysis.Through the data analysis,the exponential function model of the zone number and population quantity is established.Finally,this paper systematically summarizes and analyzes the related contents of traffic assignment and evaluation optimization.It includes four parts: initial road network informatization,traffic demand forecasting,traffic assignment and evaluation optimization.The method of road optimization in small cities mainly includes three parts: initial road network layout and inspection method,reasonable determination method of zone number,traffic assignment and evaluation optimization.