Study On Bus Priority Signal Setting For Isolated Intersection

Under the background of the development of social economy and urbanism in China, with the rapid growth of urban population and city expanding, development of urban transport infrastructure has almost reached saturation. The situation that more people and more cars sharing less land, facilities concentrated and tight space all make land resources for urban transport is extremely limited. Therefore, increasingly obvious contradiction between urban transport demand and supply exacerbates the situation of difficulty in riding or running a car. Traffic jams expands from points to lines, and lines to surfaces. At the same time, environmental problems caused by those traffic problems seriously affects the normal life of urban residents, as well as the healthy and rapid development of socio-economic. Though some large and medium-sized city's transport infrastructure can meet the transport needs of the traffic demands, the urban transport problems still need to be solved because of the rapid economic development, the development of the automobile industry and the increasing trend of urban transport motorized.Facing such serious urban transport problems, "Public Transport Priority" especially the using of it at intersection has been a powerful tool to deal with the problems of urban traffic congestion. However, with the development of method that absolute only to emphasize the priority of public transport, the limitations and problems arising from the use of process are also becoming more prominent. It still cannot be a good solution to running bus on time, as well as issues related to continuity of buses. And the measure still has a significant impact on other social vehicles and intersection operation as a whole. In today's background that extremely scarce resources needing to maximize used, the need to give absolute priority to the bus through the intersection start to be a question, and punctuality of public transport still can not have a good improvement by use of absolute priority, so the new idea of conditional bus priority come to us.First of all, the paper give an overview on the status quo of technical aspects of bus priority inland and abroad, based on this, make a described specific theoretical method in detail on specific priorities including the space priority and time priority. It introduces the bus lane set up, including setting conditions as well as sections dedicated road bus lane and intersection bus lane. In the introduction of phase design in signal design, it uses an example to show a detailed analysis of phase design of priority-based bus, and lists the flow chart. In the introduction to the signal timing design, it also give a detailed description of traditional delay model, as well as signal timing design based on public transport priority. In part of the signal design, there are also contrasts in detail between the general phase design and the phase design on bus priority, the general signal timing and bus priority signal timing.Secondly, in the core of the paper, combined with the actual situation of China, drawing on foreign models based on the quantitative methods, it gets a model based on conditional bus priority for signal timing design which is combined with the traditional model through the application of conditional bus priority. In this part, the paper mainly does some research on the weight giving to bus. Based on the relationship between the weight and the bus being late-type based on the time which was put forward by foreign scholars, according to China's grid spacing of bus-intensive features, taking into account passenger waiting time and the largest departure time interval, it reaches a new relationship between the weight and the bus being late-type based on the time. The model considers more about the actual situation of the intersection, as well as a variety of other social vehicles which also need to pass through the intersection, it is a more moderate, harmonious, and better public transport priority methods which does not use at the expense of other social vehicles.Finally, there are two parts of work have been completed: the first one is system rebuild using bus priority measures on a typical intersection from bus lane setting up to signal design has been completed; secondly, the new models drew in the core of this paper has been applied in intersection signal design, and an intersection model built with VISSIM verifies the effectiveness of the new method.This paper draws effective research results as below:(1)In this paper, the conditional bus priority has been applied, and in the calculation of weight giving to bus, the paper gives a new way considering the start of our bus interval in accordance with national conditions and determines different critical values;(2)Based on the idea of conditional bus priority, a system rebuild using bus priority measures on the actual intersection of Changchun City from bus lane setting up to signal design has been completed by the paper;(3)An intersection model built with VISSIM, which illustrated the signal phase design based on conditional bus priority. The morning peak and evening peak situation are all simulated through VISSIM including no bus priority measures and conditional bus priority, the contrast results show that signal control based on conditional bus priority features better average vehicle delay and average passenger delay.