Study On Appropriate Density Of Standing Passengers In Subway Cars

The appropriate standing passenger density in subway carriages has great influence on the subway system capacity, project cost, economic performance, comfort level, and even the passengers’safety. However, the setting of standing passenger density standard is still based on the subway system scale and project cost in China, while passengers’ comfort is rarely taken into account. This paper aims to recommend the reasonable values of standing passenger density in the respect of passengers’comfort requirements.There are several differences and defects of the researches at home and abroad on standing passenger density standard in subway carriages. With the theory of ergonomics, the factors affecting comfort in ’man-machine-environment’ system are studied, such as temperature, humidity, air quality in carriage, color, lighting, vibration, noise, space and standing time. Combined with the analysis of actual research, three indicators, which are spatial comfort, environment quality and standing time, are selected to study their quantitative relationships with the standing passenger density. First of all, a spatial comfort evaluation model and a micro-environment comfort evaluation model are developed based on standing room and air quality, respectively. Then, these two models are combined by linear weighted method, thereby developing a static comfort evaluation model. On this basis, given the impact of the standing time on passengers’comfort, the model is modified to build the generalized comfort evaluation model.Utilizing the mechanics calculation function of PFC2D, which is a particle flow software, we can simulate to verify the space comfort evaluation model. Based on individuals’requirements of comfort space in the aspects of psychology and physiology, a simulation model was developed based on the theory of social force model and the particle flow model to obtain the generalized crowded force and the distribution of passengers in different conditions of standing passenger densities. By this way, passengers’spatial comfort in subway cars can be analyzed and evaluated accurately and scientifically.Finally, based on passengers’basic comfort requirement, an optimal model is developed to determine the reasonable standing passenger density. For different subway line types, the corresponding ways to determine their reasonable standing passenger densities have been discussed, and the reasonable recommended values were proposed. The results can be utilized to guide the development of urban rail transit and the determination of standing passenger density standard for a new line so that subway carriages and subway operation can be designed more scientific and systematic.