The current wording in the text for mold sealant requires the use of wax to seal the molds to the base plates. Because of reduced time in clean up of the molds and plates, some laboratories have been experimenting with grease as an alternative to the required sealant. Data on the use of these two sealants was gathered via the CCRL Portland Proficiency Sample Program and presented to the subcommittee in the form of box plots. The plots showed that the grease produced slightly lower results that the wax. The members of the subcommittee that viewed the data felt the difference was not significant. The plots are available for review at: http://www.ccrl.us/studies/greasewaxplots.pdf Based on these presentation the subcommittee felt grease should be balloted as an alternative to the required wax sealant.
Keywordscompressive strength; hydraulic cement mortar; hydraulic cement strength; mortar strength; strength;
Ballot Item Approved