At head of title: National Cooperative Highway Research Program.

TRB's National Cooperative Highway Research Program (NCHRP) Report 568: Riprap Design Criteria, Recommended Specifications, and Quality Control examines design guidelines; recommended material specifications and test methods; recommended construction specifications; and construction, inspection, and quality control guidelines for riprap for a range of applications, including revetment on streams and riverbanks, bridge piers and abutments, and bridge scour countermeasures such as guide banks and spurs.

TRB Special Report 254 - Managing Speed: Review of Current Practices for Setting and Enforcing Speed Limits reviews practices for setting and enforcing speed limits on all types of roads and provides guidance to state and local governments on appropriate methods of setting speed limits and related enforcement strategies. Following an executive summary, the report is presented in six chapters and five appendices.