MTO AAR Reference Materials for Control, Calibration, Test Method Development and Research

The Ministry of Transportation of Ontario (MTO) has been actively involved in developing and establishing AAR reference materials for over 35 years. Currently, the primary function of these materials is for test method control and calibration for the critical purpose of ensuring the highest quality testing in support of durable Ontario infrastructure. A secondary and equally important function of these materials is to promote research into AAR. The availability and use of materials with established or “known” parameters is often essential to the success of research projects. As a result, many applied, practical and experimental researchers engaged in test method development and innovative technologies development request MTO’s AAR reference materials in support of their research programs. MTO has historically both directly and indirectly greatly benefitted from these types of external research as a result of the practice of providing reference materials. This paper provides an overview of MTO’s reference material program including its development and evolution. MTO’s new reference material code system is presented, as well as the procedure for requesting materials and MTO’s policies for making materials available to requestors. Focus is placed on the ASR reference materials past and present including each material’s physical and engineering property test ranges, geochemistry and petrography, as well as descriptions of each material’s field performance and geological environment of origin, where available.