Environment

A Methodology of Quantifying Precipitation Exposure for Wet-Weather Collisions and Evaluating Effectiveness of Open-Grade Asphalt Concrete as a Countermeasure

Chan, Ching-Yao
Jin, Eui-Jae
Oh, Soon Mi
Ragland, David R
2010

Weather-related crashes represent a significant concern in roadway safety. Wet collisions often resulted in injuries or fatalities, at a ratio higher than collisions that occur in dry roadway conditions. Therefore, it is of strong interest to identify and manage the locations where collisions are prone to happen under wet pavement surface or adverse weather conditions. This paper introduces a method to estimate precipitation exposure of roadway segments by linking weather station data to collision database. Subsequently, the corresponding crash rate for a subject location is calculated...

SafeTREC Seminar April 10: Creating Space for Bikeways: Road Diets and Parking Removal

Brazil, John
2015

The City of San Jose's Active Transportation Program is in the midst of a ten-year plan to complete a 400-mile on-street bikeway network. With more than 250 miles implemented to date, most of the easier projects have been completed. Increasingly, remaining projects are faced with constrained right-of-way without enough space to accommodate a quality bicycle facility. To create space for new bikeways, San Jose has turned to the use of road diets (removal of a travel lane to create space for other features) and/or removal of on-street parking. These projects create a number of challenges...

SafeTREC - UCTC Seminar: Flexible Work Schedules and Transportation Behavior at UC Berkeley

Ng, Wei-Shiuen
2014

Flexible work schedules could be a solution to the problems of increasing transportation demand, congestion, energy use, and carbon emissions. The higher the flexibility of work schedule, the less time employees would spend commuting to work. Hence, reducing trip frequency and total distance traveled. Flexible work schedules have been studied extensively in transportation studies, especially in areas of peak period congestion, road pricing, transit services peak and off-peak utilization, and flexibility of departure time for work. However, fewer studies have examined how the flexibility of...

Applying UrbanSim to Transportation Issues in Cities

Foti, Fletcher
2015

UrbanSim(link is external) is a software-based simulation system for supporting planning and analysis of urban development, incorporating the interactions between land use, transportation, the economy, and the environment. It is the result of over 15 years of active research, and has been applied to planning processes of over a dozen regional governments and large cities. Recent improvements to UrbanSim include an accessibility engine to compute walking-scale accessibility metrics over a metropolitan area in less than a second, and the ability to run real estate pro formas on the complete...

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,...

Documenting Targeted Behaviors Associated with Pedestrian Safety

Cooper, Jill F.
Schneider, Robert J.
Ryan, Sherry
Co, Sean
2013

The purpose of this study is to provide an exploratory analysis of the proportion of pedestrians, bicyclists, and drivers exhibiting four specific behaviors at 12 intersections near transit stations in 4 the San Francisco Bay Area. The target behaviors include: 1) pedestrians crossing the roadway while using a mobile device, such as a cell phone, 2) pedestrians crossing a signalized intersection against a red light, 3) bicyclists running a red light at a signalized intersection, and 4) automobiles turning right on red without stopping. These four behaviors are important because they may...

Giving cycling the green light: An overview of transportation in Ireland and the design of the National Cycle Network

Manton, Richard
2013

Similarly to the US, driving a car to work continues to gain ground in Ireland and the country is presented with major challenges in environment and health as a consequence. In safety, at least, Ireland has had some major successes. In 40 years, the number of fatalities has fallen from 640 to 162, a drop of 75%. Such improvements in road safety have been attributed to a combination of education, enforcement and engineering. Pedestrian and cyclist fatalities have each fallen by 66% in 20 years, however, this could be attributed to the lower numbers of people walking and cycling....

Estimating Pedestrian Accident Exposure: Protocol Report

Greene-Roesel, Ryan
Diogenes, Mara Chagas
Ragland, David R
2007

Walking is a healthful, environmentally benign form of travel, and is the most basic form of human mobility. Walking trips account for more than 8 percent of all trips taken in California, making walking the second most commonly used mode of travel after the personal automobile (Caltrans, 2002). In addition, many trips made by vehicle or public transit begin and end with walking. In spite of the importance and benefits of walking, pedestrians suffer a disproportionate share of the harm of traffic incidents in California. As noted above, walking trips make up just 8 percent of all trips in...

Evaluating the Public Perception of a Feebate Policy in California through the Estimation and Cross-Validation of an Ordinal Regression Model

Martin, Elliot, PhD
Shaheen, Susan, PhD
Lipman, Timothy
Camel, Madonna
2014

Understanding the roots of policy perception can be critical for informing the design and implementation of innovative public policies; Feebates is one such innovative policy and in the context of new vehicles can be designed to offer buyers a rebate for the purchase of low-emission vehicles and a fee for the purchase of high-emission vehicles; Because feebates is a policy that directly impacts the consumer, understanding the dynamics of public perception, support, and opposition is important; This study explores the public perception of a feebate policy within California and evaluates the...

Biofuel Boundaries: Estimating the Medium-Term Supply Potential of Domestic Biofuels

Jones, Andrew
O'Hare, Michael
Farrell, Alexander
2007

We estimate the physical supply potential of biofuels from domestic municipal solid waste, forestry residues, crops residues and energy crops grown on existing cropland using optimistic assumptions about near-term conversion technologies. It is technically feasible to produce a significant amount of liquid biofuel (equivalent to 30-100% of 2003 gasoline demand) without reducing domestically produced food and fiber crops or reducing the total calories available as domestic animal feed. Most of this supply can be attributed to the potential of energy crops, with the combination of municipal...