Research on metro platform width calculation considering the effective length of the boarding area

Addressing the limitations in the platform width calculation formula specified in the Code for Design of Metro (GB 50157-2013), this study proposes a refined method that incorporates the effective length of the boarding area and accounts for the movement patterns of passengers across various functional zones and the characteristics of passenger flow distribution. This approach charts the fluctuations in passenger flow associated with the arrival and departure of trains, producing diagrams that delineate the evolving dynamics of passenger density in the waiting and distribution areas at different intervals. By calcula ting the maximum number of pedestrians at each stage and considering the effective length, the method determines the required widths for the boarding area, the disembarking passenger's walking area, and the distribution area. An application of this modified method at a transfer station in Chengdu Metro demonstrates a reduction in maximum passenger flow density by 26.5%, 23.5%, and 3.8% in the upward waiting area, downward waiting area, and distribution area, respectively, compared to the original formula. Notably, even though the width of the distribution area remains unchanged, the modified approach still yields a lower maximum passenger flow density, indicating that congestion in the waiting area influences the distribution area. This observation underscores that, in practical applications, when the width of the waiting area cannot accommodate the queue length, the queue may extend into the distribution area, suggesting that congestion in the waiting area can propagate to the distribution area. Consequently, while the two areas are physically distinct, they are not functionally independent.