Study On Design Method Of Layout Of Connecting Line For Urban Rail Transit Based On Genetic Algorithms

ABSTRACT:With the development of Urban Rail Transit (URT), the scale of subway network has expanded continuously and the subway operation mileage is increasing. In Beijing, Shanghai and Guangzhou, their subway systems have entered the networking operation stage now. The layout of connecting line will have direct effects on the repairing of metro cars, the efficiency of rescue vehicles in different lines and the sharing of depot resources. This paper focuses on the layout of connecting line, which is in the urban rail transit network planning stage, and finishes four parts of research work as followed.(1) Based on analyzing the general functions of the connecting line, this paper focuses on the relationship between connecting lines and joint operation and depot sharing. According to the analysis of the engineering condition, construction time sequence and passenger flow organization, it is found that the setting of connecting line in joint operation can avoid the effects on the existing stations in the construction process of the forward station. The layout of connecting line should be determined comprehensively with the combination of vehicle models and repair mode on the basis of plan for depots and the sharing of resources.(2) Based on summarizing the design principle of connecting lines and the basic layout forms, the calculation method has been determined that the layout number of connecting line in different lines and network forms.(3) This paper provides an effective method for the layout of the connecting line. A model is developed to keep the cost of the connecting line being lowest based on the efficiencies of both vehicle maintenance and rescue, and the sharing of resources in different lines.(4) Based on the optimization model of the connecting line layout, this paper studies the urban rail transit network system of Chongqing in2020. Zhongliangshan vehicle plant in Chongqing undertakes the all the tasks of vehicle repairing. Using the optimization model of the connecting line based on genetic algorithm, we can set five connecting lines, which are at Bashan Station, Shapingba Station, Haixialu Station, Jiulongyuanqu Station and Tiaodeng Station. This arrangement can ensure the lowest cost of the entire network connecting lines.