Study On The Reasonable Speed Limits On Urban Expressway

How to play better functions of safety, efficiency, economy and comfort to expressway has become a hot research topic in the community. It has been proved that a reasonable speed limiting play an important role on improving the level of urban expressway safety, efficiency, economy and comfort, conversely inappropriate speed limiting play an opposite role. Currently, the management mechanism on the urban expressway is relatively backward; the formulation of the speed limiting standard is short of theoretical data as technical support. The paper tries to analysis the related theories deeply and raises the reasonable limit speed of the expressway based on running speed.The paper chooses the running speed as a basis through the analysis of the necessarily and the theoretical basis of the speed limiting. The qualitative and quantitative analyzes on the traffic flow were analyzed based on the research of the factors about speed limiting, similarly, the prediction methods of the running speed on urban expressway was proposed. On this basis, combined with visibility and psychological response characteristics of the drivers, the paper studies the standard of the minimum length on speed limiting section, the basis of the partition of the speed limiting section and the selection of the speed limiting values, simultaneously, the validity and rationality are verified by VISSIM.The research results, such as the reasonable values of speed limiting and the shortest length of speed limiting section are of reference value for the building and management department.