ASTM C1810/C1810M-20a

4.1 The results of mortar mixture tests can be suitable for comparing the relative performance of combinations of concrete-making materials such as fine aggregate, chemical admixtures, supplementary cementitious materials (SCMs), water, and hydraulic cement. Furthermore, this guide can be useful to identify unexpected performances due to combination of various materials. The relative trends in performance observed with the mortar method may suggest relative performance in concrete mixtures batched with the same materials and relative mixture proportions.

4.2 While there are a number of ways to proportion and mix mortar mixtures, two procedures described in this guide have been used extensively for evaluating the performance of admixtures. Method A enables evaluation of materials using mixture proportions that correspond to specific job conditions; whereas Method B can be used as a general mixture using fixed amounts of a standard sand, cement, and supplementary cementitious materials.

1.1 This guide provides information on how to compare the relative performance and potential incompatibility of combinations of concrete-making materials. Performance tests on fresh and early-age properties of mortar mixtures can be useful indicators of concrete performance using similar materials. The performance tests described in this guide include mortar-slump, mortar spread, mortar-workability retention, time of setting, air entrainment, and hydration kinetics.

1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with this guide. Some values only have SI units because the inch-pound equivalents are not used in guide.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.