Rationale

When testing the compressive strength of CMU and related units that will be used in loadbearing applications, it is important that the units are tested in the same direction as they will be installed in service. While this is stated in 7.4.2 Position of Specimens for 'masonry units that are 100% solid and special hollow units intended for use with the hollow cores in a horizonal condition', there is no explicit guidance in the Annexes that this also applies when testing coupons cut from the units. This is pertinent to all load bearing applications including CMU (Annex A1) SRW units (Annex A3), Grid Pavers (Annex A5) and ACB units (Annex A7). This ballot item is modifying 7.4.2 to clarify the language and adding language to the coupon testing sections of Annex A1 (CMU), A3 (SRW), A5 (Grid Pavers) and A7 (ACB). Note that no modifications are needed in Annex A2 (Concrete Brick) and A4 (Pavers) because these units are tested at a specified range of aspect ratios for which guidance is already provided in the annexes. Also, no modifications are needed in Annex A6 (Concrete Ballast Units) as these are not loadbearing applications and the compressive testing is really a 'quality of concrete' test for the units.