University of Washington

Research Highlights The rate of vehicular fatalities on rural roads is commonly twice that of their urban counterparts. One of the primary contributors to these fatalities is the passing maneuver, regarded as one of the most complex maneuvers facing motorists on rural two-lane roads and highways, particularly in the presence of dynamic horizontal and vertical curve combinations. Conversely, simply taking away passing opportunities presents the potential for reduction in capacity or level-of-service. The research being jointly conducted by the University of Alaska Fairbanks and University of Idaho aims to address the safety concerns related to passing behavior in passing zones on two-lane rural roads without diminishing roadway efficiency. Research methods will include both field and driving simulator studies. First, a mobile video data collection system will be used by the University of Alaska Fairbanks to collect real-world passing maneuvers at known problem locations in Alaska (as seen in Figure 1). Vehicle trajectory data will be extracted from the video and analyzed to determine the second-by-second speeds and locations of vehicles during passing maneuvers. This data will be used to study the effective use of passing areas, differential rates of speeds, maneuvers or trajectory changes made by oncoming vehicles, and spatial variations in passing maneuver critical points. Second, a multi-phase driving simulator study will be conducted at the University of Idaho's Human-In-The-Loop Simulation Lab (Figure 2) to capture driver passing decisions under varying geometric and environmental conditions. The collected simulator data will be supplemented with the collection of driver demographic data and participant opinions and perspectives. Two-lane rural highways represent a major percentage of the transportation network infrastructure in the Pacific Northwest PASSING ZONE BEHAVIOR AND SIGHT DISTANCE ON RURAL HIGHWAYS-EVALUATION OF CRASH RISK AND SAFETY UNDER DIFFERENT GEOMETRIC CONDITIONS region. The anticipated outcomes of this project will have direct and specific benefits for guidelines and design criteria (e.g., signage and striping needs) related to passing zones on rural curvilinear roadways. Contact: Nathan Belz, npbelz@alaska.edu The economic health of the Pacific Northwest greatly depends on domestic and international trade markets and the efficient performance of freight transportation systems and their interconnections across the region. This project synthesized information from multiple sources about the capacity of the Pacific Northwest region to handle intermodal freight transportation demand. The findings from this research are intended to be used as a framework to develop a research program focusing on the planning decision making needs of stakeholders in the region. Major sources of information about intermodal capacity were published reports from different stakeholders, online resources, and information obtained through conversations with a small set of stakeholders. Information about the current and future intermodal freight transportation demand in the region was obtained from the Freight Analysis Framework (FAF3) database of the Federal Highway Administration (FHWA) and complemented by information available in published reports. The analysis of the current and future gap between capacity and demand for intermodal freight transportation was completed using a Strength, ASSESSING THE CAPACITY OF THE PACIFIC NORTHWEST AS AN INTERMODAL FREIGHT TRANSPORTATION HUB 11 2014-2015 Annual Report

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