作者： 塞巴斯蒂安贝尔

2023年12月30日18:49https://www.carscoops.com/wp-content/uploads/2023/12/2022-City-Streets-Newspress-1-copy-1024x576.jpg

多年来,美国和其他地方的土木工程师一直在扩大交通通道,其假设是,更多的车辆空间将导致城市的安全。然而,约翰霍普金斯大学研究人员的一项新研究表明,对于城市街道来说,较窄的车道实际上可能更好。

今年早些时候发表的研究显示，在速度限制为每小时20-25英里(32-40公里/小时)的街道上,无论车道是9、10、11还是12英尺(分别为2.7、3.9、3.4或3.7米)宽,交通碰撞率并没有显著改变。然而,随着速度限制的增加,该报告的违反直觉的发现出现了。

在速度限制为每小时30-35英里(48-56公里/小时)的街道上,更宽阔的街道实际上可能是 更危险的 .研究表明,12英尺宽车道(3.7米)的街道事故率比9英尺宽车道(2.7米)的街道高出1.5倍。

阅读: Waymo的数据显示,它的无人驾驶汽车比你们人类安全6.7倍。https://www.carscoops.com/wp-content/uploads/2023/12/2022-City-Streets-Newspress-2-1024x768.jpg

"我们对城市车道宽度的研究发现,与目前的想法相反,城市地区的车道更宽,可能导致更多的车道事故。” 彭博气候智能交通中心Center for Climate-Smart Transportation at the Bloomberg School主任、博士Shima Hamidi说:"最终导致死亡。""如果我们可以在不牺牲安全的情况下缩小车道,又如何才能最好地利用现有基础设施中的额外空间呢?这就是我们想知道的。"

这项研究调查了7个美国城市7,670个街道。具有相似的平均每日交通量和可比设计特点的城市(穿过车道的数量、有中型车、街道停车等)。)。然后,它随机选择了1,117节进行分析。研究人员研究了2017-2019年期间每一节点中车道宽度与碰撞次数之间的关系。

"我们在这项研究中发现的是,当街道变得更宽的时候,就会给驾驶员一种虚假的安全感,使他们能开得更快,"哈米迪告诉公共新闻服务Public News Service的记者说

除了使街道更安全外,狭窄的街道还有其他好处。道路狭窄意味着沥青减少,这对环境有利。它们还为自行车道、人行道和更多的行人友好型基础设施提供了更多的空间。

研究人员对土木工程师和城市提出了一些建议,希望将他们的发现付诸实施。他们建议,不作为过境或货运走廊的街道路段应考虑减少道路宽度,而规划者应在低速度城市环境中默认一条10英尺宽的车道(约3米),除非有理由扩大这些路段。

他们还建议城市 适当的速度限制 对于某一特定街道段,在确定车道应多宽之前,工程师应考虑让道路向更多的使用者开放,而不是优先考虑尽可能高的安全速度。最后,应同时缩小车道,增加新的基础设施,如自行车车道和更宽的人行道。

哈米迪说:"减少道路宽度是在现有道路基础设施内容纳更好的人行道和自行车道的最简单和最具成本效益的方式。""道路狭窄,最终最大限度地减少建筑和道路维护,并减少对环境的影响。"https://www.carscoops.com/wp-content/uploads/2023/12/2022-City-Streets-Newspress-3-1024x683.jpg

原文阅读

Can Narrower Street Roads Slash Traffic Crashes? You Might Be Surprised

A Johns Hopkins study of American city streets has come to the conclusion that narrowing low-speed city streets could actually improve safety

by Sebastien Bell

December 30, 2023 at 18:49

For years, civil engineers in the United States and elsewhere have been widening traffic lanes under the assumption that more room for vehicles leads to safer cities. However, a new study by researchers at Johns Hopkins University suggests that narrower lanes may actually be better for city streets.

Published earlier this year, the study shows that on streets with a speed limit of 20-25 mph (32-40 km/h), traffic collision rates do not change significantly whether lanes are 9, 10, 11, or 12 feet (2.7, 3.0, 3.4, or 3.7 meters respectively) wide. However, the report’s counterintuitive finding emerges as speed limits increase.

On streets with a speed limit of 30-35 mph (48-56 km/h), wider streets may actually be more dangerous. Streets with 12-foot-wide lanes (3.7 meters) have accident rates 1.5 times higher than streets with 9-foot-wide lanes (2.7 meters), according to the study.

Read: Waymo’s Data Claims Its Driverless Cars Are 6.7 Times Safer Than You Humans (Sorry)

“Our study of city lane widths found that contrary to the current thinking, wider lanes in urban areas can lead to a higher number of crashes and ultimately fatalities,” said Shima Hamidi, PhD, director of the Center for Climate-Smart Transportation at the Bloomberg School, who helped lead the study. “What if we can narrow lanes without sacrificing safety, and how can we best use the additional space in the existing infrastructure? That’s what we want to know.”

The study looked at 7,670 sections of streets in seven U.S. cities that had similar average daily traffic and comparable design characteristics (number of through lanes, presence of medians, on-street parking, etc.). It then randomly selected 1,117 sections for analysis. The researchers looked at the relationship between lane width and the number of crashes that occurred in each section from 2017-2019.

“What we found in this study […] is that when streets become wider, then it gives the drivers this false sense of safety that makes them drive faster,” Hamidi told Public News Service.

In addition to making streets safer, there are other benefits to narrower streets. Narrower roads mean less asphalt, which has environmental benefits. They also leave more room for things like bike lanes, sidewalks, and more pedestrian-friendly infrastructure.

The researchers have some recommendations for civil engineers and cities that want to put their findings into action. They suggest that street sections that do not serve as transit or freight corridors should be considered for lane-width reductions, and planners should default to a 10-foot-wide lane (approximately 3 meters) in low-speed urban settings unless there’s justification for wider ones.

They also recommend that cities find a context-appropriate speed limit for a given street section before determining how wide the lanes should be and that engineers should consider making roads open to more users, rather than prioritizing the highest possible safe speed for automobiles. Finally, the narrowing of lanes should be paired with the addition of new infrastructure, like bike lanes and wider sidewalks.

“Lane-width reduction is the easiest and most cost-effective way to accommodate better sidewalk and bike lanes within the existing roadway infrastructure,” says Hamidi. “Narrower lanes ultimately minimize construction and road maintenance and also reduce environmental impacts.”