Study On Bus Timetable Optimization Based On Reliability

With the rapid development of socio-economic and the continued expansion of city size, the traffic congestion becomes even more serious. As to develop the urban public transport is the main way to ease traffic pressure, enhance its attractiveness to passengers is an urgent problem. Yet, the manifestation of this attraction is high reliability of public transport systems. At present, although study of the public transport system reliability have a certain depth, but most stay in the aspects of evaluation index system of public transit, and this reliability theory has not applied to improve the urban public transport system. To this end, we elaborated the definition of public transport system reliability, analyzed its factors and elements, and discussed the measures to improve it. Also elaborated the timetable's formulation, improved urban public transport system reliability by adjusts the bus scheduling, design optimization program of the schedule; determine the headway. Finally, we validated it with the data from the bus line 698 of Beijing. The major works are described as follows:1. Based on analyzing the engineering reliability, the definition of public transport system reliability and its representation is elaborated. Investigated the factors of public transport system, defined its three elements, and analyzed measures to improve the reliability of public transportation system.2. Based on discussing the basis and process of bus scheduling, headway is chose to be analyzed as the key problem. The methods to determine bus headway is analyzed, and time table forms are also analyzed when under different schedule forms. Also urban public transport system reliability is improved by adjust the timetable.3. An optimization program of timetable based on reliability is established. In this program, objective function is analyzed and the three elements are selected as the constraints. Algorithm is given, the headway is optimized, time table is determined, and the reliability is improved.4. Finally, the rationality and feasibility of the theories is exemplified by a case. And the results is analyzed which obtained good results.