Safety Impacts of Design Element Trade-Offs for Multilane Rural Highways
Publication: Journal of Transportation Engineering
Volume 137, Issue 5
Abstract
Roadway designs intend to provide a safe facility addressing mobility concerns, accommodating the physical and social environment and within financial constraints. Sometimes, trade-offs among these may be needed to deliver the desired project and designers need tools to estimate the safety implications from such decisions. The work completed here aimed to develop a set of recommendations to be used in evaluating safety implications from design element trade-offs. The effort focused on developing crash-prediction models and accident modification factors (AMFs) for multilane rural roads regarding lane width, shoulder width, and median width and type. The available data limited these models to four-lane roadways with 12-ft lanes. Separate models were developed for divided and undivided facilities as well as for single-vehicle, multivehicle, and all crashes involving both total and injury crashes. The AMF values recommended here were compared to those proposed in the Highway Safety Manual. Most of the proposed values are in accordance with previous work and demonstrate the effect of these elements on crash occurrence.
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Information & Authors
Information
Published In
Journal of Transportation Engineering
Volume 137 • Issue 5 • May 2011
Pages: 333 - 340
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Jan 21, 2009
Accepted: Aug 29, 2010
Published online: Sep 23, 2010
Published in print: May 1, 2011
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