Rising demand for ride-hailing services and e-commerce delivery intensifies competition for urban curbside spaces, leading to uncoordinated travel behavior, increased traffic congestion and social costs. One possible solution to address those issues is Smart Loading Zones (SLZs), equipped with advanced technologies to optimize curbside use. Yet, the real-world impact of SLZs on traffic flow is unclear due to a lack of real-world data and rigorous studies investigating SLZ’s causal effect on traffic speed. With granular speed data and real-world implementations of SLZs from Pittsburgh, PA, this study applies the regression discontinuity design method to rigorously examine the causal impact of SLZs on traffic speed in the downtown network. The results showed that the introduction of SLZs could enhance the traffic speed of the nearby road segments by 4.5%, while controlling for the underlying trend of speed and multiple influential factors such as time, weather, and road characteristics. In addition, SLZs with a short length could statistically improve traffic speed but those with a long length exert no significant effect. These heterogenous effects might be attributed to the weak enforcement at the time of SLZ deployment in Pittsburgh. The results confirmed the overall positive impact of SLZs on improving congestion. However, policies such as effective dimension planning and robust enforcement policies are essential to maximize the benefits of SLZs.

中文翻译：

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智能装载区是否有助于减少交通拥堵？匹兹堡的因果分析


对网约车服务和电子商务配送的需求不断增长，加剧了对城市路边空间的竞争，导致出行行为不协调、交通拥堵和社会成本增加。解决这些问题的一种可能解决方案是智能装载区 （SLZ），它配备了先进的技术来优化路边使用。然而，由于缺乏真实世界的数据和调查 SLZ 对交通速度的因果影响的严格研究，SLZ 对交通流量的真实影响尚不清楚。借助宾夕法尼亚州匹兹堡的精细速度数据和 SLZ 的实际实施，本研究应用回归不连续性设计方法来严格检查 SLZ 对市中心网络交通速度的因果影响。结果表明，引入 SLZ 可以提高附近路段的交通速度 4.5%，同时控制速度的潜在趋势和时间、天气和道路特征等多个影响因素。此外，短长度的 SLZ 可以统计提高交通速度，但长长度的 SLZ 没有显著影响。这些异质性影响可能归因于匹兹堡部署 SLZ 时执行不力。结果证实了 SLZ 对改善拥堵的总体积极影响。但是，有效的维度规划和稳健的执行策略等策略对于最大限度地发挥 SLZ 的优势至关重要。