safety | Transportation Research and Education Center

Traffic safety requires better engineering, education and enforcement

Feb 09, 2011

Despite some major strides in safety on Portland’s streets, the city has a lot of work remaining to make the city safe for all forms of transportation. At the fifth Transportation Safety Summit, held Feb. 8 at Marshall High School in southeast Portland, speakers stressed the importance of a multipronged approach to safety.

Sponsored by the Portland Bureau of Transportation, or PBOT, the summit also featured speakers from the Portland Police Bureau, the Oregon Department of Transportation, TriMet and Mayor Sam Adams.

Tom Miller, the incoming PBOT director, and Susan Keil, the outgoing director, said the bureau is focusing safety efforts on 10 high-crash corridors. Improving safety there will require an approach they called the “Three E’s”: engineering, education and enforcement. That is, transportation systems have to be designed for all users’ safety, the users need to know how to navigate the systems and mechanisms must be put in place to make sure people follow the rules. The city will issue annual performance reports to assess the safety of trouble spots.

According to PBOT records, citywide traffic fatalities dropped in 2010, compared to 2009. This reflects an overall trend toward fewer traffic fatalities over the last 15 years.

One worrisome point is the increase in pedestrian fatalities. The number of people killed while walking rose for the second straight year, to 15 in 2010. That’s more than the combined number of motorists, motorcyclists...

Visiting scholar wants zero traffic fatalities

Oct 13, 2010

When engineers focus on transportation systems, they often produce brilliant solutions. Sometimes, however, they focus in the wrong place.

“Engineers are really good; if you tell them, ‘This is what we want to accomplish,’ they’ll do it,” said Peter Jacobsen, himself an engineer and a public health consultant. “But traffic safety hasn’t had a good scientific, evidence-based approach that we have in, say, nuclear-power-plant design.”

Jacobsen, Portland State University’s first visiting scholar this school year, will present the Vision Zero concept at Friday’s transportation seminar. Vision Zero resets the goal of transportation systems from reducing total crashes to eliminating fatalities.

“The way engineers currently look at the road system is to look at crashes,” Jacobsen said. “Vision Zero folks say to look at health: not to have fatalities or permanent disabling injuries.”

Designing for health means respecting the limits of the human body. If crossing into oncoming traffic could produce head-on collisions with a greater force than people could survive, then Vision Zero says to separate that traffic. Roundabouts reduce the likelihood of dangerous side-impact collisions.

Vision Zero could have the largest effect closer to home. Jacobsen has pushed for colleagues to consider traffic from a child’s perspective. A residential street that might be...

Geometric Design, Speed, and Safety

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In this seminar, Dr. Porter will explore the interactions of geometric design decisions, speed, and safety. A performance-based approach to this topic will be considered given the availability of several key documents, including the Highway Safety Manual and TRB's Modeling Operating Speed: Synthesis Report as well as a significant body of published research. A historical look at the design speed concept will show that while the design speed definition has changed on more than one occasion, the same basic but flawed philosophy that relates design speed to a “safe speed” is still reflected in supplemental guidance related to design speed selection in current design policy. A conservative approach to establishing design criteria, currently used to address the range of driver, vehicle, and roadway conditions and capabilities that a designer must consider, will be demonstrated. Resulting operating speeds will be shown to be higher than design speeds for design speeds of approximately 55 mph or less. This outcome may be considered undesirable...

Oregon DOT Jurisdictionally Blind Safety Program

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Douglas Bish, Traffic Engineering Services Unit Manager with ODOT, will discuss the Jurisdictionally Blind Safety Program. This program is a safety program designed to address safety needs on all public roads in Oregon. The aim of the program is to foster collaboration between local road jurisdictions, to increase increase awareness of safety on all roads, promote best practices for infrastructure safety, compliment behavioral safety efforts and focus limited resources to reduce fatal and serious injury crashes in the state of Oregon. This seminar will introduce some of the details of the program.

Imbalances in Lane Change Accommodation Time and Lasting Disturbances

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Classic highway traffic flow theory can explain the evolution of signals and waves once they form. Given sufficient boundary conditions the theory captures the evolution of the traffic state over space and time. But one rarely finds such ideal boundaries on real highways. Often disturbances arise within a region that classic theory would tell us should be homogeneous. These disturbances often grow and give rise to unstable traffic upstream, e.g., resulting in stop-and-go conditions during congestion with an increased frequency of accidents. This talk will examine one potential source of these disturbances, namely the fact that after a lane change maneuver drivers accommodate an entering vehicle quicker than a departing vehicle (mandatory accommodation versus discretionary accommodation). After illustrating this imbalance on two facilities, the talk will explain how it can give rise to lasting disturbances.

Dr. Coifman is an associate professor at the Ohio State University with a joint appointment in the department of Civil and Environmental Engineering and Geodetic Science and the Department of Electrical Engineering. His research emphasizes extracting more information about traffic flow both from conventional vehicle detectors and emerging sensor technologies. His work has been recognized by the ITS America Award for The Best ITS Research and an NSF CAREER award. Dr. Coifman...

Lighten Everyone's Load: LIDAR Applications to Support Engineers, Planners, Scientists and More

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Light detection and ranging (LIDAR) technology is reshaping the civil engineering profession and offers many unique advantages. National efforts such as the 3D Elevation Plan (3DEP) are helping increase the availability of LIDAR data. LIDAR is one of the crucial technologies that is transitioning the world of civil and construction engineering from 2D paper-based design to 3D digital design. The high spatial resolution and accuracy capabilities of LIDAR have led to increased efficiencies, improved analyses, and more informed decision making.

A further advantage of this dataset is that multiple people can use the same dataset for a variety of purposes across multiple disciplines. The visual nature of the dataset also is more intuitive than traditional data acquisition and analysis techniques. This presentation will provide a brief background of LIDAR , its capabilities, limitations and platforms, and discuss its current and future role in civil engineering. Examples of a wide range of transportation, geotechnical, coastal, and structural engineering, science, and planning applications will be presented including development of mobile LIDAR guidelines for...

Do perceptions match reality when riding in a green lane?

By Jennifer Dill, Ph.D.
Professor, Urban Studies & Planning
Director, TREC

This week I’m at the International Travel Survey Conference in Australia. The conference happens every three years, attracting over 100 geeky people who spend time thinking about things like stated preference experiments, smartphone data collection, combining sampling frames, and respondent burden. I presented some work from our five city Green Lanes project, comparing our survey data with “objective” measures, such as videos and traffic counts. The focus was on intersections, where the protected lane is no longer separated from motor vehicles. An example of one design used in Portland, OR is shown in the adjacent figure.

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Some of the comparisons are...

Oregon's Statewide Work Zone Traffic Analysis Program

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Retrofitting Urban Arterials Into Complete Streets

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Abstract: The geometric design of our urban arterials and collector streets can provide more room for nonmotorized travelers, make street crossings easier for pedestrians, and help to control traffic speeds, thus reducing pedestrian, bicycle and automobile crashes. In this seminar Mr. LaPlante will show how this can be done within existing rights-of-way and within tight maintenance and construction budgets, thus making better use of taxpayer dollars. The seminar also will address some of the myths about Complete Streets and how we can begin moving forward in making all our street networks complete.

Speaker Bio: John LaPlante is currently Director of Traffic Engineering for T.Y.Lin International, working out of their Chicago office. Prior to joining the firm in 1992, Mr. LaPlante had been with the City of Chicago for 30 years in various transportation engineering positions, including Chief City Traffic Engineer and Acting Commissioner of the new Department of Transportation. He has been involved in several national committees (PROWAAC, AASHTO Green Book Technical Committee, NCUTCD Pedestrian Task Force, and the TRB Pedestrian Committee) and was principal author of the AASHTO Pedestrian Guide. He has taught many courses as part of the...

Long Before Airline Deregulation

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