AASHTO - American Association of State Highway and Transportation Officials
Scope
This Guide for Pavement Friction was prepared under NCHRP Project 1-43 to provide highway pavement practitioners with guidance in designing@ constructing@ and managing pavement surfaces??as part of both new and rehabilitation projects??that meet the public's demand for safe friction levels@ while recognizing and considering the effects of noise generation and other pavement?C tire interaction issues (e.g.@ splash and spray@ tire wear). The guide contains recommendations and tools for upper-level administrators and policy-makers@ as well as front-line pavement designers and managers. These recommendations are intended to supplement but not replace an agency's normal structural and/or mix design practices. The guide covers the following topics: Characteristics of pavement materials and surfaces that contribute to adequate wet-weather friction; Friction-testing methods@ equipment@ and indices; Methods for establishing friction levels that signify (a) design of new pavement surfaces@ (b) increased potential for skid-related crashes@ and (c) the immediate need for friction restoration; and Guidance for aggregates@ mixtures@ and surface types that result in long-lasting@ high-quality friction surfaces@ with proper consideration of noise@ economics@ and other friction-related issues (e.g.@ splash and spray@ hydroplaning@ tire wear). The guide addresses both asphalt (i.e.@ flexible and semi-rigid) and concrete (i.e.@ rigid) pavements associated with both original construction (i.e.@ new construction and reconstruction) and maintenance and rehabilitation (MR) treatments. It does not address winter maintenance issues (i.e.@ snow and ice removal/treatment) and does not deal with unpaved surfaces or nonhighway pavements.