Infrastructure

We All Want the Same Thing Results from a Roadway Design Survey of Pedestrians, Drivers, Bicyclists, and Transit Users in the Bay Areav

Sanders, Rebecca L.
Cooper, Jill F.
2012

Pedestrians, bicyclists, drivers, and public transit users all desire similar roadway design features, at least according to findings from a recent intercept survey of 537 people along a major urban corridor in the San Francisco Bay Area. This research was sponsored by the California Department of Transportation to understand traveler preferences for street design that could increase perceived traffic safety, walkability, and bikability along urban arterials, as well as encourage economic vitality through increased patronage of local businesses. In an open-ended question about street...

Oakland Chinatown Pedestrian Scramble: An Evaluation

Bechtel, Allyson K
MacLeod, Kara E.
Ragland, David R.
2003

In 2002, the City of Oakland, California implemented a scramble signal, at the intersection of 8th Street and Webster Street. Scrambles are a type of traffic signal that give pedestrians exclusive access to an intersection by stopping vehicular traffic on all approaches, allowing pedestrians to cross diagonally or conventionally. The primary objective of this evaluation was to determine whether the installation of the pedestrian scramble at this location increased pedestrian safety. An analysis was conducted of pedestrian-vehicle conflicts and pedestrian violations occurring at the...

Collaboration Math: Enhancing the Effectiveness of Multidisciplinary Collaboration

Cohen, Larry
Aboeleta, Manal
Gantz, Toni
Van Wert, Jennifer
2003

Reducing the toll of traffic-related injuries requires a concerted effort, calling on the resources, commitment and expertise of diverse agencies, professionals and community members. Traffic safety is affected by numerous aspects of community life such as how neighborhoods are designed, how fast cars travel and how safe people feel walking or driving to key destinations. Preventing traffic-related injury is a responsibility shared by many. As evidenced by many federal, state and local efforts, partnerships, coalitions and networks have become common ways to address the incidence of...

Pedestrian and Bicyclist Safety Effects of the California Safe Routes to School Program

Gutierrez, Nicolas
Orenstein, Marla
Cooper, Jill
Rice, Thomas
Ragland, David R.
2008

In the last decade, there has been an increased focus in California on encouraging children to walk and bicycle to school safely. In 1999, the California Legislature created the Safe Routes to School (SR2S) program, authorizing issuance of a competitive grant process for roadway construction projects. There has been an overall decline in the numbers of child pedestrian/bicyclist collisions in California as a whole. When compared with the control areas, the SR2S project areas did not show a greater decline in numbers of collisions. However, it is likely that the number of children walking/...

Pilot Models for Estimating Bicycle Intersection Volumes

Griswold, Julia B.
Medury, Aditya
Schneider, Robert J.
2011

Bicycle volume data are useful to practitioners and researchers to understand safety, travel behavior, and development impacts. This paper describes the methodology used to develop several simple models of bicycle intersection volumes in Alameda County, California. The models are based on two-hour bicycle counts performed at a sample of 81 intersections in the Spring of 2008 and 2009. Study sites represented areas with a wide range of population density, employment density, proximity to commercial property, neighborhood income, and street network characteristics. The explanatory variables...

Single-Vehicle Fatal Crash Prediction for Two-Lane Rural Highways in the Southeastern United States

Zhu, Hong
Dixon, Karen K.
Washington, Simon
Jared, David M.
2010

The rural two-lane highway in the Southeastern United States is frequently associated with a disproportionate number of serious and fatal crashes and as such remains a focus of considerable safety research. The Georgia Department of Transportation spearheaded a regional fatal crash analysis to identify various safety performances on two-lane rural highways and offer guidance for identifying suitable countermeasures to mitigate fatal crashes. The fatal crash data used in this study were compiled from Alabama, Georgia, Mississippi, and South Carolina. The database, developed for an earlier...

Providing Intersection Decision Support under Challenging Conditions

Shladover, Steven E.
VanderWerf, Joel
Ragland, David R.
2006

This paper describes the results of simulation studies to determine how effectively left-turning drivers can be alerted to imminent conflicts with opposing traffic under difficult operating conditions and with limited detector capabilities. These conditions include approaching vehicles changing speed in locations that are not covered by detectors and detectors that may only be able to detect vehicle presence, but not speed. In cases without direct speed detection, one may try to rely on historical speed statistics to estimate the speed of approaching traffic, but unless the approach speeds...

San Pablo Avenue Pedestrian Signal Timing Optimization

Nguyen, Ahn
Ragland, David R.
2007

The focus of this study is to quantify the sufficiency of “Flashing Don’t Walk” (FDW) intervals at signalized pedestrian crossings in the San Pablo Avenue (SPA) corridor in Northern California. Our goal is to determine if pedestrian signal intervals on the SPA corridor can be optimized in a way that makes the pedestrian crossing environment safer and more comfortable for all pedestrians without diminishing vehicular throughput. This study provides a corridor-wide as well as a city-by-city assessment of FDW intervals on the SPA corridor. We suggest a possible tool to assist traffic control...

Pedestrian and Bicycle Safety Strategies for UC Berkeley Campus and Periphery: Recommendations for Implementation

Schneider, Robert J.
Grembek, Offer
Braughton, Mathew
Orrick, Phyllis
Ragland, David R.
2013

The high level of pedestrian, bicycle, and transit activity on city-owned streets surrounding the UC Berkeley campus creates a dynamic social environment and gives Berkeley much of its charm. But the streets around the campus (henceforth called the campus periphery) are also places where pedestrians and bicyclists have been injured or killed in collisions with automobiles. This creates liability for drivers, the City, and the University—and worse, causes suffering for crash victims and their families. Everyone has an interest in reducing the frequency and severity of pedestrian and bicycle...

Cross-Section Designs for the Safety Performance of Buffer-Separated High-Occupancy Vehicle (HOV) lanes

Jang, Kitae
Kang, Sanghyeok
Seo, Jongwon
Chan, Ching-Yao
2011

High-occupancy vehicle (HOV) lanes have been deployed as a tool for traffic management in urban freeway systems to improve reliability and mobility of trips. As they are planned to traverse crowded urban areas, it is often difficult to acquire sufficient right-of-way for retrofitting HOV lanes to existing freeway systems with recommended cross-sectional design. The present study proposes a methodology to determine the optimal set of cross-sectional design for safety performance by evaluating individual impact of each design element on safety as well as tradeoffs between them. Detailed...