Mini-Mix Mortar Mixtures
Concrete technologists need to have a well-defined, useful and efficient means to detect and possibly address concrete material incompatibility issues. This need will be addressed in a proposed new ASTM International standard, WK40615, Practice for Mixing and Comparing Performance of Concrete Materials Using Mini-Mix Mortar Mixtures.
Due to an increased focus on sustainability, the emergence of new technologies and the decreasing availability of suitable materials in some regions, a wider range of materials is now being used in concrete production. WK40615 will be used to test the potential performance of these new materials.
According to ASTM member Ara Jeknavorian, Jeknavorian Consulting Services, WK40615 will comprise two methods for preparing mortar mixtures. "Adding the capability of this standard to the overall quality assurance program of a concrete producer will provide the general public and the concrete industry an increased sense of confidence that the concrete supplied for various construction projects will more consistently meet the required performance standards," says Jeknavorian.
Jeknavorian notes that WK40615 will more than likely be used in one of three ways:
- To act as an ongoing quality control tool to verify lot-to-lot performance uniformity for various concrete materials;
- To proactively screen the performance of a new or alternate source material under consideration; and
- To troubleshoot an unexpected performance issue, assuming the materials associated with the problem are still available.
WK40615 is being developed by Subcommittee C09.48 on Performance of Cementitious Materials and Admixture Combinations, part of ASTM International Committee C09 on Concrete and Concrete Aggregates. All interested parties are invited to participate in the standards developing activities of C09.48. The subcommittee is particularly interested in contributions from those using paste and mortar mixtures to help predict changes in concrete performance when a material property changes.
"C09.48 is a collaboration between C09 and ASTM Committee C01 on Cement, which underscores the mutual responsibility across material suppliers and testing agencies to help improve the predictability of the performance of concrete materials," says Jeknavorian. "The work of C09.48 can be greatly enhanced by concrete producers sharing their own experiences in dealing with material incompatibility issues."
CONTACT Technical Information: Ara A. Jeknavorian, Ph.D., Jeknavorian Consulting Services • • Phone: 617-803-2612 | ASTM Staff: Scott Orthey • Phone: 610-832-9730 | Upcoming Meeting: Dec. 7-10 • December Committee Week • New Orleans, La.