Model And Method For Timetabling Problem Of Bus Rapid Transit System To Improve Level Of Service

With the increasing of traffic congestion, Bus Rapid Transit (BRT) has been developed rapidly in many cities. Till now, BRT lines have been operated in a number of cities in China, including Beijing, Hangzhou, Changzhou, Zhengzhou, Chengdu, and so on. In addition, the total length of BRT lines has reached 2800km.Although BRT system contains exclusive lanes, high-capacity vehicles, intelligent operation management system, and advanced passenger service system, there are still many factors which affect the normal operation of BRT system. The fluctuation of travel time, signal control at intersections, and coordinated operation between BRT lines and conventional bus lines have a significant impact on the BRT operation management, which lead to the decrease of operation efficiency and level of service of the BRT system. Therefore, considering the characteristics of BRT, the theory and method to solve the BRT timetabling problem are further studied to improve the level of service. This study will enrich and deepen the bus operation management theory. Also, it is a meaningful exploration to release urban traffic congestion.On the basis of domestic and foreign research on BRT operation management, the concept of level of service and the characteristics of BRT system are discussed. The theory and method of scheduling design are analyzed with the consideration of influencing factors of level of service:road section, intersection, and operation coordination. The main studies are as follows:(1) BRT timetable design theory on the basis of level of service is studied. Based on the analysis of BRT operation system, especially for hardware, software and operation organization system, the operation characteristics are described. Then, the relationship between timetable and level of service is analyzed and the impact of timetable on BRT level of service is discussed. Furthermore, the theory of BRT timetable design based on level of service is proposed, including the influencing factors and the key technology in the design process.(2) BRT schedule design method based on the travel level of service is studied. Considering the basis of bus schedule design and the common methods, the method based on the time control is proposed for BRT schedule design. To improve the travel level of service on the road section, the travel characteristics of BRT vehicles are analyzed and the method to determine the travel time is proposed. After the travel time is calculated, the method to design BRT schedule is put forward. In this method the principles and standards of BRT schedule design are the key analysis points. The model for BRT schedule design are proposed based on the travel level of service on the road section. The objective function and constraints of the optimization model are provided. The intelligent calculation method, named as shuffled frog leaping algorithm, is used to solve the model. The results show that the method can effectively improve level of service.(3) Optimization model and algorithm for BRT schedules design based on the level of service at intersections is proposed. With the consideration of BRT control methods at intersections, the relationship between control parameters and BRT schedules are analyzed according to the features of signal intersection. Based on the travel level of service at intersections, an optimization model for BRT schedule design is proposed and the objective function and constraints are provided. The research results show that the dwell time of BRT vehicles at intersections is greatly reduced by the schedule adjustment. Also, the probability of BRT vehicles through the intersection during the green time is increased.(4) Optimization model and algorithm for BRT schedule design based on coordinated operation is proposed. On the basis of BRT schedule design methods considering level of service on the road section and at intersections, the concept and function of coordinated operation between BRT and other transit systems are analyzed. Then the approach and objective to achieve coordinated operation are further proposed and the optimization model and algorithm are developed. The research results show that the feeder bus routes are able to reserve the predetermined transfer time at the transfer stations. Moreover, on the section which requires capacity coordination, BRT lines can provide service with a certain departure interval. These methods effectively improve the level of service.