Materials Reference Library

The Materials Reference Library (MRL) is a storage facility that houses highway materials from the LTPP program's general pavement studies (GPS) and special pavement studies (SPS). Asphalt and portland cement, natural aggregates, and combinations of these materials in both loose and core form are stored in the MRL, along with LTPP distress film. An MRL inventory list of GPS and SPS materials, along with general information on the MRL and forms for requesting material are available from the MRL.