城市道路路段行人立体过街设施设置条件研究

A Warranty Analysis of Grade Separated Pedestrian Crossings of Urban Roadways

为合理设置路段行人立体过街设施,保障过街行人安全,对某双向6车道主干路无信号人行横道处的过街行人等待时间、交通冲突时间及行驶车速进行了视频观测。定义了机动车流消散时间计算公式,根据调查获取的过街行人忍受等待时间阈值,给出了设置路段行人立体过街设施的机动车流率条件。基于调查数据,采用回归分析法构建了交通冲突时间与行驶车速的关系模型,依据安全行车所需满足的制动距离与冲突距离的关系,给出了设置路段行人立体过街设施的行驶车速条件。依据计算得到的信号控制人行横道设计通行能力,给出了设置路段行人立体过街设施的行人流率条件。研究结果表明,当机动车高峰时段每个信号周期内任意1个行驶方向机动车流消散时间大于60s,或行驶车速大于50km/h,或过街行人流率大于2 200人/(hg·m)时,应考虑设置路段行人立体过街设施。

In order to set grade separated pedestrian crossing facilities reasonably on urban road sections and ensure the safety of crossing pedestrians,the video observation method was used to obtain the waiting time of crossing pedestrians,traffic conflicting times and driving speeds at an un-signalized crosswalk on an arterial road with two-way six lanes.Calculation formula of vehicle dispersing time was proposed,and the warrant of traffic volumes was defined for grade separated pedestrian crossing facilities according to investigated threshold value of crossing pedestrians′tolerable waiting time.Based on observed data,regression method was applied to establish relationship model between pedestrian-vehicle traffic conflicting times and vehicle driving speeds.The warrant of driving speed for grade separated pedestrian facilities was determined based on the relationship between stopping sight distances and the width of conflict zones.The warrant of pedestrian volumes was defined by calculated design capacity of signalized crosswalks.The results show that grade separated pedestrian crossing facilities are warranted when vehicles' dispersing time of any direction is more than 60 sduring one cycle in peak hour,or driving speed is more than 50km/h,or crossing pedestrian volume is more than 2 200person/(hg·m).