Browsing by Subject "Highway design"

Now showing 1 - 3 of 3
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    Benefit:Cost Analysis of In-Vehicle Technologies and Infrastructure Modifications as a Means to Prevent Crashes Along Curves and Shoulders
    (Minnesota Department of Transportation, Research Services Section, 2009-12) Pitale, Jaswandi Tushar; Shankwitz, Craig; Preston, Howard; Barry, Michael
    The State of Minnesota has under way its Toward Zero Deaths (TZD) initiative, the goal of which is to eliminate fatal traffic crashes. This is a daunting task, and with limited financial resources, optimal strategies that provide the greatest benefit for a given cost have to be utilized if the goal of TZD is to be met. This report reviews both infrastructure and emerging in-vehicle solutions as a means to determine the optimal deployment strategy of countermeasures designed to improve highway safety. Infrastructure-based solutions are examined on two levels: 1) an analysis of a cross-section of strategies implemented throughout Minnesota, which 2) produced a before:after analysis that quantified the effectiveness of a variety of strategies utilized in Minnesota. In addition to the standard civil engineering countermeasures studied under the before:after analysis, emerging infrastructure and in-vehicle technology-based solutions were modeled in terms of effectiveness and potential deployment schedules. These cost and effectiveness models facilitated a comparison to the results of the before:after analysis, and from the comparison, optimal strategies for improving safety with limited funds and the TZD goal are presented.
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    Criteria and Guidelines for Three-Lane Road Design and Operation
    (Minnesota Department of Transportation, 2023-02) Davis, Gary A.; Hourdos, John; Gao, Jingru
    A 4-3 conversion involves changing a four-lane undivided road into one with two general travel lanes separated by a two-way left turn lane. A commonly-used guideline states that a 4-3 conversion can be considering as long as the road’s average annual daily traffic (AADT) volume does not exceed 15,000 vehicles/day but opinions vary, from lowering the AADT threshold to 10,000 vehicles/day to anecdotal evidence for successful 4-3 conversions with AADTs as high as 20,000. The main objective of this project was to identify conditions where 4-3 conversions might be feasible at AADTs greater than 15,000. After reviewing the literature, we conducted simulation studies on three different roads to identify combinations of major and minor road flow where three-lane configurations provided acceptable levels of service. Eight intersections, with 16 approaches, were then selected to represent our findings. These results were presented as summary tables that practitioners could use to make initial assessments regarding 4-3 conversion feasibility.
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    Investigating the Effects of Roadway Design on Driver Behavior: Applications for Minnesota Highway Design
    (Minnesota Department of Transportation, 1999-02) Scallen, Stephen; Carmody, John
    This report details a project to study the relationship between highway design and human behavior as influenced by roadside environments. In a visualization phase, computer simulation modeled an actual segment of urban highway planned for reconstruction in Tofte, MN Using a driving simulator, project design team members test drove the highway reconstruction project and evaluated the planned elements. In an experimentation phase, researchers tested drivers' responses to different design scenarios to identify the architectural and aesthetic elements with the greatest potential for calming or slowing traffic. Results indicated that the visualization phase increased communication among project team members and state agencies, facilitated problem Identification-resolution strategy development, and contributed to decision-making concerning potential design options and design elements. Data also indicated that white pavement treatments produced desirable traffic calming effects. Analyses of drivers' speed patterns indicated a consistent speed profile, characterized by both decreases and increases in speed. The report concludes with recommendations for the expanded use of visualization in general and the implementation of white pavement treatments in the target reconstruction project specifically. It also recommends further consideration of landscape architecture treatments.