Research On The Optimization Of Operation Coordination Under Collinear Condition Of Bus And Rail Transit

Under the background of urban stock renewal,vigorously developing efficient public transportation is the key to alleviate traffic congestion.Major cities aim to build a public transport network with rail transit as the skeleton and conventional buses as the main body.However,the auxiliary operation of conventional bus is seldom considered in the process of rail transit construction and operation,thus the section of long-distance co-running between conventional bus and rail transit appears.The resulting unhealthy competition hinders the coordinated development of public transport,and it is urgent to optimize its operation from the perspective of public transport fusion line network,so as to form a mutually reinforcing and benign cooperation public transport network system.Due to the physical characteristics of rail transit,it is difficult to adjust after completion,so the common line bus is usually optimized.However,there are few studies that comprehensively consider the race-cooperation relationship between rail and bus and the travel choice factors of passengers in the converged line network,and most of them are based on virtual example network or single mode network,and the accuracy is low with the use of survey data.In this paper,by analyzing the race-cooperation relationship between rail and bus and the travel choice behavior mechanism of passengers in the public transport composite network,a co-linear bus optimization model considering multiple factors will be constructed and applied to the actual network.The main research contents and conclusions are as follows:Firstly,the characteristics of rail transit and conventional buses are compared.The competition and cooperation between rail and bus are analyzed in detail from the perspective of spatial topology and travel space-time distribution.This paper expounds the optimization strategy of conventional bus route,station layout and operation organization.The optimization method of this paper is determined as operation organization optimization,which provides theoretical basis for the study of optimization model.Then,in order to study the mode choice behavior of passengers in the composite network,five multinomial Logit models considering the combination of multiple factors are constructed from the perspective of route choice.Using the big data of traffic trips on a working day in Beijing in 2016,the complete travel chain of passengers in the composite public transport network is extracted,and the route choice is aggregated into the mode choice.The parameter calibration and model selection are carried out by taking the commuter travel group in Haidian District as an example.The calibration results show that the choice model based on complete trip is superior to the choice model based on trip stage.The mode choice behavior of commuters on the composite public transport network is significantly correlated with the total travel time and ticket price factors,and the total travel time has a greater impact.The forms of cost function and travel option in the optimization model are determined to provide data basis for the optimization model.Finally,based on the above work,a co-line bus operation organization optimization model considering passenger travel cost,bus operation cost and rail-bus competition intensity is constructed.The method selection is introduced into the model to improve the accuracy of the model.In order to make the model more reasonable,the constraint conditions considering the departure interval and bus load factor are established.Combined with the characteristics of the model,genetic algorithm was used to solve the problem.The section from Beigongmen to Dongwuyuan of Beijing Subway Line 4 and the section from Beigongmen to Dongwuyuan of common bus line 332 in Haidian District of Beijing in 2016 are taken as an example to conduct optimization case analysis.The results show that after optimization,the objective function value is reduced by 23.54%,and the competitive intensity value is reduced by 0.207.The model can effectively improve the public transport service level and coordination ability.The research of this paper is based on composite network to meet the needs of public transportation network development.The proposed mode choice model considers the combined mode of travel and can reflect the characteristics of passengers’ travel choice behavior in the composite network.The co-linear bus optimization model takes passenger’s travel choice into consideration and can more truly reflect the implementation effect of the optimization strategy.The model considers the competition intensity index of rail and bus,and the research results can provide technical support for improving the coordination degree of rail and bus,and improve the overall competitiveness of public transport.