New Environmentally-Friendly Cement Type
The 2009 edition of the CSA A23.1 Concrete Materials and Methods of Concrete Construction Standard references a new class of cement called "Portland-limestone cement" (PLC). While PLC has been used in Europe for over 25 years, it is new to Canada. This follows the introduction of PLC to the 2008 edition of the CSA A3000 Cementitious Materials Compendium Standards. The updated CSA cement and concrete standards have been referenced in the 2010 NBCC, which was published in November of 2010. Currently, Portland-Limestone Cement has been approved for use in BC, Ontario, Quebec and Nova Scotia. Once other provincial jurisdictions adopt the 2010 NBCC, or update their references to the current cement and concrete standards, portland-limestone cement will be accepted by building authorities in those jurisdictions as well. Portland-limestone cement is being rebranded as Contempra in Canada.
Portland-limestone cement reduces greenhouse gas emission associated with existing cement manufacturing by approximately 10%, while producing concrete with similar strength and durability characteristics to that achieved with existing GU cements. The industry will move to have PLC recognized in the LEED building rating system as reducing the clinker content of the cement in concrete and in so doing qualify for LEED credits. In its initial offering, PLC cements will not be permitted in sulphate exposure environments until further testing in combination with supplementary cementing materials (SCMs) verifies conclusively its performance under these conditions.
For more information, view following files.
Portland-limestone Cement General Overview (40-minute presentation) 5.7 Mb
Portland-limestone Cement Overview Notes (40-minute presentation) 46.94 Kb
Portland-limestone Cement Brief Overview (20-minute presentation) 808.73 Kb
Portland-limestone Cement Brief Overview Notes (20-minute presentation) 37.19 Kb