VTechWorks staff will be away for the winter holidays starting Tuesday, December 24, 2024, through Wednesday, January 1, 2025, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!

Browsing by Author "Smith, Kelly L."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Improving Highway Safety Through Pavement Friction Management Programs
    Smith, Kelly L.; Larson, Roger M.; Flintsch, Gerardo W.; Sherwood, Jim (2012)
    In recent years, there has been a major increase in activities related to improving highway safety in the U.S. Much of the emphasis has been placed on driver behavior (e.g., addressing aggressive, distracted, and impaired driving and the neglected use of seat belts) and roadway design (e.g., geometrics, roadside, and traffic control features), and this has led to updated FHWA regulations and guidance regarding the Highway Safety Improvement Program and major research publications, such as the NCHRP 500-series reports (Guidance for Implementation of the AASHTO Strategic Highway Safety Plan) and the 2010 American Association of State Highway and Transportation Officials (AASHTO) Highway Safety Manual (first edition). A similar upswing in activities has taken place with regard to the safety of pavement surfaces. Following efforts in the mid-1990s to comprehensively examine pavement surface characteristics (PSCs) (e.g., texture, friction, noise, hydroplaning potential), FHWA has developed policy guidance for Surface Texture for Asphalt and Concrete (Technical Advisory T5040.36) (2005), AASHTO has published the Guide for Pavement Friction (2008), and FHWA has developed policy guidance on Pavement Friction Management (Technical Advisory T5040.38) (2010). Building off these and other PSC-related technical advancements, and recognizing the need to apply pavement friction management (PFM) concepts and technologies in the U.S., the FHWA has sponsored a major, multi-year study to develop and demonstrate PFM programs at four state highway agencies (SHAs) using guidance contained in the AASHTO Guide for Pavement Friction. In Phase 1 of the two-phase study, a review of past efforts of quantifying the relationship between friction/texture and crashes was done, along with a review of both U.S. and International pavement safety programs/practices. In addition, a detailed evaluation of currently available friction/texture measurement equipment was performed to identify those best suited for the PFM programs to be developed in Phase 2 of the study. This paper discusses the examination of past studies investigating the friction/texture– crash relationship and the review of pavement safety programs/practices. It presents the main conclusions of these two research activities, as they relate to the planned development of PFM programs in four states (yet to be identified).
  • Thumbnail Image
    Splash and Spray Assessment Tool Development Program: Final Report
    Flintsch, Gerardo W.; Tang, Lijie; Katicha, Samer W.; de León Izeppi, Edgar; Viner, Helen; Dunford, Alan; Nesnas, Kamal; Coyle, Fiona; Sanders, Peter; Gibbons, Ronald B.; Williams, Brian M.; Hargreaves, David; Parry, Tony; McGhee, Kevin K.; Larson, Roger M.; Smith, Kelly L. (Virginia Tech. Virginia Tech Transportation Institute, 2014-10-07)
    The effects of vehicle splash and spray are well known to motorists who have driven in wet weather conditions. Research suggests that splash and spray contribute to a small but measurable portion of road traffic accidents and are the source of considerable nuisance to motorists. Splash and spray from highway pavements also can carry a number of pollutants and contaminants. When deposited, these contaminants can be poisonous to plant life and accelerate the corrosion of roadway appurtenances. Splash and spray are individually definable processes that are the product of a number of different factors. Many parties have gone to great lengths to reduce the splash and spray created by motor vehicles, especially that from heavy vehicles, by retrofitting devices that alter the vehicle’s aerodynamics. Another possible solution to the problem is to change the characteristics of the highway pavement. Previous research shows that pavement geometry, drainage, texture, and porosity all contribute to splash and spray generation, but the exact mechanisms are largely unknown. A model capable of predicting the splash and spray propensity of pavements can be used by highway engineers to support decisions in highway maintenance and design. The project objective was to develop a simple and practical assessment tool to characterize the propensity of highway sections to generate splash and spray during rainfall and the impact of splash and spray on road users. This report summarizes the development of the splash and spray model and its implementation in an easy-to-use, practical tool.