A study on effects of bus rapid transit operation improvement in Bangkok

Bus Rapid Transit (BRT) is considered to be one of the sustainable transportation modes to mitigate congestion problem in many megacities as well as developing cities. BRT requires low cost of construction and operation compared to other modes of mass transit systems. This present study consists of five major objectives, which were to identify problems occurring on the BRT corridor in Bangkok, create and calibrate a traffic simulation model to represent the realistic condition, suggest appropriate solutions and evaluate their effects using the developed simulation model, identify the influenced factors to improve the BRT service based on the perceptions of the BRT users using exploratory factor analysis (EFA), and provide recommendations for BRT improvement for city planners and decision-makers. Data for evaluation of BRT operation was collected from the on-site and on-board survey, and data for evaluation travel characteristics and influence factors were collected using questionnaires. This present study developed the microscopic simulation model by using AIMSUN software and calibrated by adopting the simple two-parameter search algorithm. According to the operational problem, the study proposed three possible solution to improve the operation of BRT in Bangkok, which were applying transit signal priority (TSP), enforcing fully segregate lane (FS), and adding additional lane as a reversed lane (RL). The evaluation of this study concerned the two hours in the morning peak (7:00 am – 9:00 am) and two hours in the evening peak (16:00 pm – 18:00 pm).Regarding EFA result of the study, it indicated that the factors that should be improved in order to gain more attractive of using BRT, which were the operational improvement factor, service improvement factor, and other improvement factor with regards to cost and safety issue. The operational factor was prioritized to improve prior to other factors. This factor consisted of applying ITS system at the at-grade intersections, upgrading the condition of buses and stations, operating in the segregated lane (BRT lane only), and accessing the BRT information easily. In which, the factor helped to confirm that the operational issue should be deeply in concern. Regarding the evaluation of traffic simulation analysis, it revealed TSP solution was beneficial for both BRT and cars in the corridor. While the FS solution could provide the positive impact only for the BRT. Since one lane from inbound direction and outbound direction were dedicated to the BRT. Besides, the RL solution returned the positive impacts to the direction that the lane is reversed, since this solution was to add one additional lane by reversing the lane in the opposite direction that was not congested as another lane. Therefore, this present study recommended the TSP solution as the most recommended solution to improve the operation of the BRT in Bangkok. Since this solution had the most positive impact to the network in term of travel time saving among three solutions. The findings from this study could be applied as a baseline information for decision making and transportation planning in improving BRT operation in Bangkok.