These guide specifications provide guidance for developing transportation contract specifications and are the national standard for best practices in highway and road construction. This consensus-based guide ..... Read More
This 2020 3rd edition includes the following revisions and updates from the previous 2015 2nd edition: new fracture mechanics-based model for reflective cracking in AC overlays over flexible, ..... Read More
The AASHTO Materials Standards contain specifications, test methods, and provisional standards commonly used in the construction of highway facilities.
The Materials Standards are updated three times ..... Read More
The Transportation Research Board (TRB) typically has more than 200 active research projects underway at any given time. The majority of these are contract research projects administered by the TRB’s Cooperative Research Programs, which includes the National Cooperative Highway Research Program (NCHRP). NCHRP conducts research in problem areas that affect highway planning, design, construction, operation, and maintenance nationwide.