ABSTRACT

In recent years, bikesharing has become one of the most popular policies promoting cycling across the world. As the number of bikesharing systems (BSS) continues to rise, it is increasingly important to quantify their expected benefits. This paper synthetises the available evidence on the current impacts of implementing a BSS, with a special focus on the induced modal shift dynamics and impacts in car reduction, indicating how increasing the attractiveness of BSS to car users could improve its benefits. Several benefits have been associated to bikesharing, but they are not equally distributed and are dependent on several nuances, particularly on modal shifts. Among the biggest contributions are the increases in physical activity (PA) levels (triggering health gains) as well as travel time savings to the BSS users. Bikesharing is mostly replacing sustainable modes of transport, with modest car replacing rates. However, bikesharing can also indirectly decrease car travel by fostering synergies with Public Transport (by expanding catchment areas, reducing overcrowding and overall travel times) and by promoting cycling use through increasing the number and diversity of cyclists. Furthermore, different types of modal shift lead to different benefits. Reductions in car travel induce decreases in greenhouse gases (GHG) and other air pollutants, increases in PA, time savings as well as congestion reductions. Conversely, new trips generated by BSS also lead to increases in PA, while modal shift from walking to BSS has been associated with travel time savings. Shifting PT users to BSS can also reduce overcrowding in saturated PT networks. The most social disadvantaged groups were found to be systematically under-represented among BSS users, yet equity measures combined with awareness-raising campaigns could increase usage rates. Exploring potential advantages of BSS against car use and increasing its car replacing rates, coupled with better impact assessments, should constitute research priorities.

摘要

近年来，共享单车已成为在世界各地促进骑行的最受欢迎政策之一。随着自行车共享系统（BSS）的数量不断增加，量化其预期收益变得越来越重要。本文综合了有关实施BSS的当前影响的现有证据，特别关注了诱发的模态换档动力学以及对减少汽车的影响，表明增加BSS对汽车使用者的吸引力可以如何改善其利益。共享单车带来了一些好处，但是它们分配不均，并且取决于一些细微差别，特别是取决于模式转换。最大的贡献之一是身体活动（PA）水平的增加（触发健康增长）以及为BSS用户节省的旅行时间。共享单车主要是用适度的汽车替换率来代替可持续的交通方式。但是，共享自行车还可以通过促进与公共交通的协同作用（通过扩大集水区，减少人满为患和总体旅行时间）以及通过增加骑自行车者的数量和种类来促进骑自行车的使用，从而间接减少汽车旅行。此外，不同类型的模式转换会带来不同的收益。减少汽车旅行会导致温室气体（GHG）和其他空气污染物的减少，PA的增加，节省时间以及交通拥堵的减少。相反，由BSS产生的新行程也导致PA的增加，而从步行到BSS的模式转换已与节省旅行时间相关联。将PT用户转移到BSS还可以减少饱和PT网络中的拥挤情况。发现社会最弱势群体在BSS用户中代表性不足，但是公平措施与提高认识的运动相结合可以提高使用率。探索BSS对抗汽车使用的潜在优势并提高其汽车更换率，再加上进行更好的影响评估，应该成为研究的重点。