Land Use and Built Environment

Evaluation of Countermeasures: A Study on the Effect of Impactable Yield Signs Installed at Intersections in San Francisco

Banerjee, Ipsita
Ragland, David R.
2007

The present study evaluated the effect of impactable signs that used the yield-symbol as approved by the National Committee on Uniform Traffic Control Devices (NCUTCD) in the 2003 Manual of Uniform Traffic Control Devices (MUTCD). Impactable yield signs are low- costsignsconstructed of flexible material. The signs wereinstalled in the medians adjacent to crosswalks at selected non-signalized intersections to instruct drivers to yield the right-of-way to pedestrians. This paperexamines the effect on safety characteristics of the intersections of these signs at three stop-sign controlled...

Low Cost Upgrades to At-Grade Crossing Safety Devices

Cooper, Douglas L
Ragland, David R
Felschundneff, Grace
2013

The only way to absolutely prevent all drivers from going around lowered gates at level rail-highway crossings is to make it physically impossible, or at least very difficult, for them to do so. While there are various options to accomplish this (constructing a separation of grade, closing the crossing, or deploying an impenetrable concrete barrier), most have high monetary or social costs. Alternative approaches—such as channelization devices and long-arm gates—while not 100 percent effective, can be used to prevent deaths and injuries while remaining economically feasible. Research has...

Roadway and Infrastructure Design and Its Relation to Pedestrian and Bicycle Safety: Basic Principles, Applications, and Benefits

Ragland, David R
Grembek, Offer
Orrick, Phyllis
Felschundneff, Grace
2013

Road deaths are forecast to double by 2020, with the burden falling most heavily on low- and middle-income countries and, within those countries, on the most vulnerable and poorest road users. Half of the 1.2 million people killed and 50 million injured in road crashes each year are pedestrians, motorcyclists, bicyclists, and users of unsafe public transport; and more than 90 percent are from low- and middle-income countries. Because these are the areas where rapid motorization is taking place, the issue of safety in increasingly multi-modal environments is now of critical importance,...

Do All Roadway Users Want the Same Things?

Sanders, Rebecca L
Cooper, Jill F
2013

This paper presents findings from a recent study on roadway design preferences among pedestrians, drivers, bicyclists, and public transit users along a major urban corridor in the East San Francisco Bay Area. Sponsored by the California DOT, the research focused on exploring design preferences that could increase perceived traffic safety, walkability, bikability, and economic vitality along urban arterials. Results from an intercept survey showed that all user groups desire similar roadway design features along the test corridor, which carries 25,000-30,000 motorists bi-directionally and...

Compliance, Congestion, and Social Equity: Tackling Critical Evacuation Challenges through the Sharing Economy, Joint Choice Modeling, and Regret Minimization

Wong, Stephen D.
2020

Evacuations are a primary transportation strategy to protect populations from natural and humanmade disasters. Recent evacuations, particularly from hurricanes and wildfires, have exposed three critical evacuation challenges: 1) persistent evacuation non-compliance to mandatory evacuation orders; 2) poor transportation response, leading to heavy congestion, slow evacuation clearance times, and high evacuee risk; and 3) minimal attention in ensuring all populations, especially those most vulnerable, have transportation and shelter. With ongoing climate change and increasing land development...

Going My Way? Understanding Curb Management and Incentive Policies to Increase Pooling Service Use and Public Transit Linkages in the San Francisco Bay Area

Darling, Wesley
Broader, Jacquelyn
Cohen, Adam
Shaheen, Susan, PhD
2023

Despite lower user costs, only 20% to 40% of transportation network company (TNC) users select a pooled, or shared, ride option. Why are existing TNC users not selecting the pooled option or using TNCs to connect to public transit, and what role do built environment features and incentives play in their decision? This study explores the factors that influence TNC user decisions through a multi-method approach comprising photovoice small group discussions and a workshop. Between March 2021 and May 2021, 15 San Francisco Bay Area TNC users shared photographs they took of TNC pick-up...

Carsharing and the Built Environment: Geographic- Information System-Based Study of One U.S Operator

Stillwater, Tai
Mokhtarian, Patricia L.
Shaheen, Susan A.
2009

The use of carsharing vehicles over a period of 16 months in 2006-07 was compared to built environment and demographic factors in this GIS-based multivariate regression study of an urban U.S. carsharing operator. Carsharing is a relatively new transportation industry in which companies provide members with short-term vehicle access from distributed neighborhood locations. The number of registered carsharing members in North America has doubled every year or two to a current level of approximately 320,000. Researchers have long supposed that public transit access is a key factor driving...

Personal Vehicle Sharing Services in North America

Shaheen, Susan A.
Mallery, Mark A.
Kingsley, Karla J.
2012

Over the past three decades, carsharing has grown from a collection of local grassroots organizations into a worldwide industry. Traditional carsharing, though expanding, has a limited network of vehicles and locations. The next generation of shared-use vehicle services could overcome such expansion barriers as capital costs and land use by incorporating new concepts like personal vehicle sharing. Personal vehicle sharing provides short-term access to privately-owned vehicles. As of May 2012, there were 33 personal vehicle sharing operators worldwide, with 10 active or in pilot phase,...

EasyConnect: Low-Speed Modes Linked to Transit Planning Project

Shaheen, Susan A. PhD
Rodier, Caroline J. PhD
2006

The EasyConnect Low-Speed Modes Linked to Transit Planning Project (TO 5113) project represents the integration of innovative strategies to enhance transit use during the development and construction of a suburban transit oriented development at the Pleasant Hill Bay Area Rapid Transit (BART) District station in the East San Francisco Bay Area. This planning project brings together a unique partnership including small technology businesses, transportation agencies, city and county government, and academia. The project components include the introduction of shared-use low speed mode...