Infrastructure

Evaluation of Traffic and Environment Effects on Skid Resistance in California

Oh, Soon Mi
Madanat, S M
Ragland, David R.
Chan, Ching-Yao
2010

Skid resistance is one of the important serviceability indicators related to safety on wet pavements. There is a need to manage skid resistance systematically to maintain the level of safety performance of roadway surfaces. This study focused on the development of a skid resistance deterioration model based on the analysis of skid data inventory collected in California. The California Department of Transportation (Caltrans) has collected skid resistance data across the complete state highway network over the past two decades using a standard locked-wheel skid trailer, ASTM E-274. This...

The Marked Crosswalk Dilemma: Uncovering Some Missing Links in a 35-Year Debate

Mitman, Meghan Fehlig
Ragland, David R.
Zegeer, Charles V.
2008

Largely in response to several landmark safety studies, as an official or unofficial policy, many agencies across the U.S. have elected to remove marked crosswalks at uncontrolled intersections, or have shown resistance to installing them in the first place. This approach results in unacceptable pedestrian mobility restrictions, yet such restrictions are often not considered in policy-making. As such, there is a need for roadway system owners to develop strategic safety guidelines to address the marked crosswalk dilemma. Since 2005, the UC Berkeley Traffic Safety Center, in a study funded...

The Effects of Transportation Corridor Features on Driver and Pedestrian Behavior and on Community Economic Vitality: Final Study Report

Sanders, Rebecca L. PhD
Griffin, Ashleigh MS, MCP
MacLeod, Kara E. MHP
Cooper, Jill F. MSW
Ragland, David R. PhD, MPH
2012

This report presents the results from a multiyear effort to develop and test performance measures for evaluating the impact of landscaping and roadside features on pedestrian and bicyclist safety and mobility and economic vitality for Caltrans’ urban arterial network. The first phase of the study was a literature review, and the second phase focused on developing performance measures. The third and fourth phases focused on testing the proposed performance measures consisting of an infrastructure analysis, policy review, safety analysis and a pedestrian and bicyclist intercept survey on two...

Airports and Bicycles: what are the obstacles and incentives for operators 1 to improve bicycle access?

Orrick, Phyllis
Frick, Karen Trapenberg
2013

In this paper we use a case study approach to examine how airport operators are addressing bicycle access to their properties and the motivations and obstacles they face, in light of new policies to integrate bicycles, along with transit and walking, into transportation planning, design and construction, and to increase bicycles’ role in the transportation system. Eight influential elements emerged from our review of policy documents and research literature. We used them to guide interviews with key informants. The eight elements are: governance structure, location, access roads, self-...

Develop a Plan to Collect Pedestrian Infrastructure and Volume Data for Future Incorporation into Caltrans Accident Surveillance and Analysis System Database

Zhang, Yuanyuan
Proulx, Frank R.
Ragland, David R.
Schneider, Robert J.
Grembek, Offer
2014

This project evaluates the feasibility of developing a pedestrian and bicycle infrastructure database and volume database for the California state highway system. While Caltrans currently maintains such data for motor vehicles in the Traffic Accident Surveillance and Analysis System - Transportation System Network (TASAS-TSN) database, the agency does not keep records on pedestrian or bicycle facilities. This information is crucial for improving the safety of these vulnerable road users. This project developed a proposed database structure and corresponding data collection methodology. It...

Social Equity Impacts of Congestion Management Strategies

Shaheen, Susan, PhD
Stocker, Adam
Meza, Ruth
2019

This white paper examines the social equity impacts of various congestion management strategies. The paper includes a comprehensive list of 30 congestion management strategies and a discussion of equity implications related to each strategy. The authors analyze existing literature and incorporate findings from 12 expert interviews from academic, non-governmental organization (NGO), public, and private sector respondents to strengthen results and fill gaps in understanding. The literature review applies the Spatial – Temporal – Economic – Physiological – Social (STEPS) Equity Framework (...

Understanding Evacuee Behavior: A Case Study of Hurricane Irma

Wong, Stephen
Shaheen, Susan, PhD
Walker, Joan, PhD
2018

In September 2017, Hurricane Irma prompted one of the largest evacuations in U.S. history of over six million people. This mass movement of people, particularly in Florida, required considerable amounts of public resources and infrastructure to ensure the safety of all evacuees in both transportation and sheltering. Given the extent of the disaster and the evacuation, Hurricane Irma is an opportunity to add to the growing knowledge of evacuee behavior and the factors that influence a number of complex choices that individuals make before, during, and after a disaster. At the same time,...

Exploring the Future of Integrated Transportation Systems in the United States from 2030 to 2050: Application of a Scenario Planning Tool

Shaheen, Susan, PhD
Camel, Madonna
Lee, Kunik
2013

Intelligent transportation systems (ITS) have primarily focused on systems management. To further improve connectivity and safety in the future, ITS might embrace a more holistic planning approach. While the future of ITS remains an open question, its evolution is closely linked to how the world evolves on many dimensions, social, political, economic, legal, and environmental. In this paper, the authors present results from four expert workshops. These consisted of an initial steering committee workshop (February 2011), two expert scenario-planning workshops (June 2011), and a final...

Policy Brief: Social Equity Impacts of Congestion Management Strategies

Shaheen, Susan, PhD
Stocker, Adam
Meza, Ruth
2019

To better understand the equity implications of a variety of congestion management strategies, researchers at the Transportation Sustainability Research Center (TSRC) at University of California, Berkeley analyzed existing literature on congestion management strategies and findings from 12 expert interviews. The literature review applies the Spatial – Temporal – Economic – Physiological – Social (STEPS) Equity Framework1 to identify impacts and classify whether social equity barriers are reduced, exacerbated, or both by a particular strategy. The congestion management strategies of...

The Benefits of Carpooling

Shaheen, Susan, PhD
Cohen, Adam, MCRP
Bayen, Alexander, PhD
2018

Carpooling allows travelers to share a ride to a common destination and can include several forms of sharing a ride, such as casual carpooling and real-time carpooling. Because carpooling reduces the number of automobiles needed by travelers, it is often associated with numerous societal benefits including:1) reductions in energy consumption and emissions, 2) congestion mitigation, and 3) reduced parking infrastructure demand. In recent years, economic, environmental, and social forces coupled with technological innovations are encouraging shared and pooled services. Shared mobility is...