个体出行情景下上海中心城区地铁可达性研究

地铁是城市内重要的公共交通方式,对缓解交通压力、提高居民出行便捷度起到重要作用。个体通过地铁前往城市内不同地点的能力受个体前往地铁站的能力和地铁站间的通行能力影响。基于此,该文综合考虑个体可达性与地方可达性,提出评价个体到达区域内不同地点能力的指标——个体区域出行可达性,即从某点出发就近进入某类交通网络节点,通过该交通网络到达该网络所有节点的最短时间均值,可结合最短旅行时间及加权平均旅行时间计算得到,以尽可能精细地评价在节点分布足以代表区域的情形下个体到达整个区域的能力,并计算了上海中环以内城区地铁出行的个体区域出行可达性。结果表明:受线网结构和自然地物分布的影响,个体在上海中心城区通过地铁前往不同地点的能力由最中心地区向外波动下降,部分特殊地区和线网稀疏区个体出行能力较差,浦西地区的可达性情况明显好于浦东地区。

Research on Metro Accessibility in Central Urban Area of Shanghai under Individual Travelling Scenario

As an important kind of public transport,metro contributes to alleviating traffic pressure and improving residents′travel convenience a lot.Mainly focusing on individuals′ability to get to metro stations or accessibility between metro stations,present research on metro accessibility has some deficiencies in evaluating residents′ability to get to different places in the city.Therefore,we proposed an evaluation index,"personal regional travelling accessibility",defined as"The shortest average time it takes to travel from a point,to a node in close proximity to a traffic network,and to reach all traffic nodes through that traffic network",to calculate the convenience of individuals′travelling to different places in the city by metro.In case the nodes make them enough to be a representation of the area,the personal regional travelling accessibility can be calculated by combining the weighted mean travel time which represents how difficult to arrive at other metro stations in the research area from the initiative station,and the shortest travel time which indicates the convenience to the nearest metro station.Based on metro travel time collected from the APP"Metro Daduhui",the personal regional travelling accessibility of metro in the central urban area of Shanghai was calculated.It is found as follows.Individual travel ability is mainly affected by the distribution of natural features and metro lines.The personal regional travelling accessibility decreases with fluctuation from city center to outside,the value of accessibility in some places which is far from metro stations or with special natural features is relatively low,meanwhile accessibility in Puxi is much better than that in Pudong.