A Study On BRT Network Planning And Optimal Frequency Based On Intelligence Optimization Algorithms

Presently the Bus Rapid Transit in China has shifted into the growing-up stage from the beginning. The plan, construction and operation of BRT have been the focus of the many sectors including urban plan bureau and public transit corporation. In recent years, intelligent optimization algorithms have been newly developed and applied in solving the problems of BRT plan and frequency optimization. In this dissertation, the difference between BRT and traditional transit being considered, there are the researches on BRT network optimization, frequency optimization of stratagem, frequency optimization of tactics,combined routes optimization, etc.The main contents are as follows.1. A kind of BRT networks plan models for nonstop passenger flow maximization based on the problem characteristics is given. A tabu search algorithm as the solution is designed. The algorithm applies the coding by natural number to OD match, routes generation and vehicle numbers assignment to get original solution. And routes choosing and vehicle assignment respectively do with BRT routes and frequency with penalty function and neighborhood operation to resolve restrictions. In this part, a network planning with 20-stop BRT is simulated. Algorithm parameter regulation and repetition calculation are done for analyses.2. The BRT passenger flow distribution in one day is as Double-Peak, and the frequency in different periods must be adjusted for reasonable configuration of transportation capacity from the angel of stratagem planning, so a model considering the benefits of operator and passengers is built and the improved Genetic Algorithm for the problem is given. Simulation optimization based on the genetic algorithm is designed through betterment crossover and mutation operation. A simulation optimization research is given in which the effect of waiting time weight value to the result is as an analysis.3. From the angle of Transit Company as an economic entity, the competition between BRT and other transit mode is considered. Based on the calculation of cost function by ticket price, vehicle speed and frequency, an improved logit assignment method is applied to optimize the frequency and maximize the transit company benefit to keep the passengers'satisfaction service level. A mathematical model and solution algorithm based on tabu algorithm is designed for the transit dispatching with competition. In the tabu algorithm, nature coding is designed to divide one day into multiple periods so as to cut the solution set to parts according to the periods. And constrains of shift between different frequencies and unique shift are operated as two neighborhoods. Without change of fundamental parameters, vehicle speed and ticket price are changed to influence the simulation results.4. For the standard routes and pass-by bus combination, considering the competition from other modes, especially traditional transit, it is to optimize the frequency and maximize the transit company benefit for keeping the passengers'satisfation service level. Based on the characteristics of the problem, simulated annealing algorithm is combined with tabu search algorithm to optimize the frequency of BRT line combination. The combined tabu-simulated-annealing algorithm applies 0-1 coding to represent pass-by stops set and natural number to represent standard routes and frequency. According to BRT combined routes characteristic, the neighbor states of back single point, 2-swap exchange and add-cut single point are designed with 2-swap tabu table and single point tabu table. Then optimization simulation research is given for combined routes.