Proposed Cementitious Materials Standard Will Facilitate Materials Blending
A proposed new ASTM International standard will facilitate the blending of different supplementary cementitious materials. The proposed standard, WK12964, Specification for Blended Supplementary Cementitious Materials, is being developed by Subcommittee C09.24 on Supplementary Cementitious Materials, under the jurisdiction of ASTM International Committee C09 on Concrete and Concrete Aggregates.
When supplementary cementitious materials are blended, a synergistic effect can be created that results in a strong, durable concrete. However, because there has been no standard that allows the blending of materials, the use of blending technologies has been limited to large producers who have multiple silos. WK12964 will enable a greater number of producers, including those with just one silo, to take advantages of the benefits of blending materials.
“Blending to optimize performance will ultimately encourage the use of supplementary cementitious materials in concrete and therefore support the growth and acceptance of sustainable building practices,” says Gregory Daderko, product manager, Lafarge.
Supplementary cementitious materials that can be blended include slag conforming to ASTM standard C 989, Specification for Ground Granulated Blast-Furnace Slag for Use in Concrete and Mortars; natural pozzolans and fly ash conforming to C 618, Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete; and silica fume conforming to C 1240, Specification for Silica Fume Used in Cementitious Mixtures.
According to Daderko, WK12964 will have two primary applications. First, the standard will allow concrete producers that are silo-constrained to have the same performance capabilities for blending that producers with multiple silos have. Also, the proposed standard will allow a material supplier to create a product that can be optimized for performance.
Because of these applications, the most likely users of the proposed standard will be silo-constrained concrete producers and supplementary cementitious material suppliers that have access to multiple products and have the desire to produce a blended product to meet customer needs.
Daderko says that the task group working within Subcommittee C09.24 on WK12964 currently has good participation, with different disciplines well represented, but that anyone interested in the topic who is willing to work is always welcome. “We are always looking for knowledgeable, hard working individuals willing to participate, with the objective of meeting industry needs and making our standards better,” says Daderko. //
Technical Information: Gregory Daderko, Lafarge Company, Herndon, Va.
ASTM Staff: James Olshefsky
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