Research On Pedestrian Walkway Capacity In Mountainous Cities

Mountain city is a special kind of cities around the world.Compared with plain cities,its terrain and environmental conditions are more complex,and its traffic and transportation problems are also more difficult.Therefore,it is of great significance to transportation planning and management of mountain cities.As an important component of the urban transportation system,sidewalks are the main passage for pedestrians to travel.In mountainous cities,the use of sidewalks by residents accounts for a large proportion of travel modes,and the capacity of sidewalks directly affects the efficiency and safety of pedestrian travel.This article conducts research on the pedestrian capacity of mountainous cities,which can better understand the factors that affect pedestrian traffic,improve pedestrian traffic efficiency and safety,and is of great significance for urban residents’ travel.Firstly,by reviewing relevant regulations on urban construction in China,local regulations in Chongqing,and literature,combined with preliminary survey results,the longitudinal slope of pedestrian walkways in mountainous cities is classified into grade A(0-4%),grade B(4-8%),grade C(8-12%),grade D(12-16%),and grade E(16-20%).Divide pedestrian categories into groups based on pedestrian gender,age,and walking direction.A total of 3030 pedestrian walking speed data and 559 stride and stride frequency data were obtained from 7 pedestrian walkway survey points in Chongqing through on-site investigation and manual data extraction.Based on the above measured data,the average walking speed of pedestrians in mountainous cities is analyzed to be1.07m/s.The pedestrian walking speed on the sidewalk with slope grade A is the highest,at 1.18m/s.When the sidewalk slope is grade E,the average walking speed of pedestrians decreases to 0.94m/s,and the overall trend of the average walking speed of pedestrians is to decrease with the increase of slope.Using the ANOVA test,the significance of gender,age,and walking direction on pedestrian walking speed in pedestrian walkways with different grades of slope was obtained.Through comparative analysis of pedestrian stride frequency and stride size in plain cities,it was found that the stride size of pedestrians in mountainous cities is usually between 0.40 m and 0.90 m,with a stride frequency of approximately 107 steps per minute.Both data are smaller than the corresponding parameters of pedestrians in plain cities.Secondly,using plain cities as a reference,qualitative analysis was conducted on the characteristics of pedestrian walkways in mountainous cities to identify 10 influencing factors on pedestrian capacity in mountainous cities.According to the measured data of sidewalk under different influencing factors,the judgment matrix of each influencing factor is obtained by combining Delphi method method.Based on this,the Analytic Hierarchy Process(AHP)model was used to calculate and analyze 10 influencing factors in a hierarchical manner.Finally,it was determined that pedestrian slope,pedestrian width,and the proportion of downstream pedestrian flow were the main influencing factors on pedestrian capacity in mountainous cities.Then,analyze the capacity of the pedestrian walkway under the three main influencing factors determined.Using Levenberg Marquardt optimization algorithm,basic graph method,and measured data,the Underwood model was selected for data fitting and parameter solution.The calculated maximum flow rate of the sidewalk in 1minute was converted into hourly flow rate as the measured capacity of the sidewalk.The calculation results indicate that under certain other conditions,the slope of the sidewalk is negatively correlated with the capacity,and the capacity value always increases with the increase of width and the proportion of downstream pedestrian flow.Finally,in order to further investigate the impact of the three main influencing factors on pedestrian capacity,Vissim software was used to simulate pedestrian capacity under different conditions multiple times,in order to calculate the pedestrian capacity under each influencing factor.According to the simulation results,it was found that the longitudinal slope of the sidewalk at 8.0% is the turning point slope where the traffic capacity significantly decreases;When the width increases from 5m to 7m,the increase in capacity under various slope conditions slows down;After the proportion of downstream pedestrians exceeds 60%,the increase in the capacity value of sidewalks on each slope is more significant.A comprehensive analysis was conducted on the main influencing factors of pedestrian walkways in mountainous cities.Based on a multiple linear regression model,a comprehensive capacity calculation model was established using Matlab software based on the longitudinal slope gradient,width,and proportion of pedestrians descending.The model passed the MAPE and RMSE index tests,and then used to provide recommended capacity values for pedestrian walkways in mountainous cities with widths of 3m and 4m.In summary,the research results of this article can provide reference for the formulation of design specifications for urban pedestrian walkways under mountainous conditions,and make a certain contribution to the sustainable development of cities.