RFI#012: Cementing Materials

Question:

Clause 7.2.2: All concrete used in toboggan construction must be comprised of cementitious materials containing a minimum of 30% Portland cement by mass.

Does the 30% portland cement by mass includes the mass of fly ash, silica fume or other cementitious materials?

Answer:

The quoted clause is being updated in an upcoming rule revision. The updated clause is as follows:

All concrete used in toboggan construction must be comprised of at least 30% cementing materials by mass. Cementing materials are any materials having cementing properties or contributing to the formation of silicate compounds. Examples include portland cement, hydraulic cement, fly ash, slag, silica fume, and metakaolin.