Engineering Commons^™

Current Efforts To Make Bike Share More Equitable: A Survey Of System Owners And Operators, Steven Howland

PSU Transportation Seminars

The number of public bike share systems has been increasing rapidly across the United States over the past five to ten years. To date most academic research around bike share in the U.S. has focused on the logistics of planning and operationalizing successful systems. Investigations of system users and impacts on the local community are less common, and studies focused on efforts to engage underserved communities in bike share are rarer still. This paper utilizes a survey of representatives from 55 U.S. bike share systems to better understand and document current approaches toward serving low income and minority populations. The …

Webinar: Improving Walkability At Signalized Intersections With Signal Control Strategies, Edward J. Smaglik, Sirisha Murthy Kothuri

TREC Webinar Series

The goal of signal timing at an intersection should be to maximize efficiency for all users. In many jurisdictions, however, traffic signals are timed mostly with the goal of reducing vehicular delay.

Other road users, such as pedestrians, deserve similar focus. In legacy transportation systems, pedestrians experience delays much in excess of those that would be deemed acceptable for a motor vehicle at the same location.

Excessive delay can lead to pedestrian frustration, non-compliance and ultimately decreased safety.

In the North American context, implementation of strategies to address pedestrian service varies greatly across jurisdictions, and there has been limited research …

Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen

PSU Transportation Seminars

The problem of bus bunching in a high frequency service has been largely studied in the literature.

This phenomenon is produced by three main factors

(i) the variability in travel time between stops; (ii) variations in passenger demand; and (iii) drivers’ heterogeneity.

In order to tackle this phenomenon a wide range of control strategies have been proposed, however, none of them had been successfully implemented on a large transit network with high frequency services.

In this talk, we present a control scheme based on a rolling horizon optimization problem that has been successfully implemented for real-time control of two high …

Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper

Civil and Environmental Engineering Master's Project Reports

Vehicle speed has long been one, if not the primary contributing factor to crashes, influencing both the probability and severity. Within the Portland metro area arterials have the highest serious crash rate per road mile and vehicle miles travelled. (Metro, 2012) The purpose of this research is to compile vehicle speeds along select arterial roadways within the Portland metro area and comparing it to applicable crash data. The roadway segment of SE Foster Road between SE 52^nd avenues and SE 82^nd avenues was selected, due to the simplicity of the physical as-built roadway properties along with available Bluetooth …

Feasibility Determination Guide For The Road Diet Plus: A Five/Four-Lane To Two-Lane Road Diet, Michael Williams

Civil and Environmental Engineering Master's Project Reports

Road diets are a popular tool for corridor improvement. Road diets are normally defined as the conversion of a four-lane undivided road to a three-lane undivided road made up of two through lanes separated by a center two-way-left-turn-lane (known as a TWLTL). This new configuration has similar vehicular capacity, greater safety and frees up right-of-way for other uses.

This work examines the possibility of going one step, or one lane, further. What is the possibility of reducing five- or four-lane roads to two-lanes? If this is possible, what are the corridor characteristics within which this process would be feasible?

The …

Improving Walkability Through Control Strategies At Signalized Intersections, Sirisha Murthy Kothuri, Andrew Kading, Edward J. Smaglik, Christopher Sobie

TREC Final Reports

As cities and communities nationwide seek to develop Complete Streets that foster livability and accommodate all modes, signal timing control strategies that include pedestrians in the operational decision process are gaining importance. This research tested several efficiency-focused pedestrian treatments – coordination, actuated-coordination, free operation, short cycle lengths – and safety-focused treatment including leading pedestrian intervals and Barnes Dance. Using a software-in-the-loop simulation, the operational impacts of these treatments on all users (vehicles, heavy vehicles, bicyclists and pedestrians) at an intersection were evaluated. Results showed that among the efficiency-based treatments, free operation was most beneficial for reducing minor-street pedestrian delays. Both …

A Practitioner's Guide To Urban Trip Generation, Kristina Marie Currans

TREC Project Briefs

In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously used across the US and Canada. Only recently, with the third edition of the ITE Trip Generation Handbook, have new data and approaches been adopted. In this study NITC researcher Kristina Currans takes aim at understanding issues inherent in the collection and application of ITE’s data and methods in various urban contexts. This technology transfer guide touches on the main findings from this work.

Issues In Trip Generation Methods For Transportation Impact Estimation Of Land Use Development: A Review And Discussion Of The State-Of-The-Art Approaches, Kristina Marie Currans

Civil and Environmental Engineering Faculty Publications and Presentations

As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate and robust means for estimating transportation impacts for site-level development review. This paper is a review of the state-of-the-art trip generation methods for land use transportation impact estimation. First, it provides an overview of the more recent available and peer-reviewed estimation methods. Second, the authors offer a discussion of the successes of state-of-the-art approaches using common themes of research to identify corresponding consistency with theories of travel behavior and urban economics. These themes …

Accessibility, Income, And Person Trip Generation: Multilevel Model Of Activity At Food Retail Establishments In Portland, Oregon, Kristina Marie Currans, Kelly Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall person-trip rates at similarly-sized establishments of the same land use do not vary across a region. This is an assumption of convenience to permit the adjustment of ITE Trip Generation vehicle trip rates for use in different urban environments. However, this assumption is inconsistent with theories of urban economics, which recognize that businesses pay a premium to locate in areas with high levels of accessibility to attract more customers. In …