TRB's National Cooperative Highway Research Program (NCHRP) latest Research Topic Highlights explores solutions for roadway tunnels. It summarizes the results of several research projects that has framed the problems and mitigation strategies associated with tunnels. Included are summaries of tunnel inspection, rehabilitation, and preservation; tunnel design; and tunnel safety and security.

TRB's National Cooperative Highway Research Program (NCHRP) latest Research Topic Highlights explores Bank Erosion and Bridge Scour. It summarizes the results of several research projects to better quantify and model the mechanisms of bridge scour. Included are summaries of bank erosion and countermeasures, bridge scour countermeasures, predictive equations for scour, and special cases involving scour.

TRB's National Cooperative Highway Research Program (NCHRP) latest Research Topic Highlights explores the use and application of Warm Mix Asphalt (WMA). This fact sheet summarizes the use of WMA and applications in the past decade. WMA is produced at temperature that is cooler than hot mix asphalt (HMA), reducing worker exposure to asphalt fumes as well as reducing emissions. The publication provides an overview of how NCHRP research has addressed questions about WMA performance, evaluated WMA compared t...