Masonry Magazine February 1993 Page. 24
Compressive strength is a prime consideration in concrete, but it is only one of several important factors in mortar. Once the proportions of cementitious materials and sand are established, and appropriate compliance tests are conducted, it is important that batch to batch variations are controlled within acceptable limits. Construction site testing procedures permit establishment of conformance to proportions of ingredients and quality control of mortar production. Strength testing provides verification that mortar is performing normally.
Test results obtained under ASTM C780, however, are not required to meet the minimum compressive strength requirements of ASTM C270, Property Specification.
REFERENCES:
ASTM C91, Specifications for Masonry Cement, American Society for Testing and Materials
ASTM C109, Compressive Strength of Hydraulic Cement Mortars, American Society for Testing and Materials
ASTM C270, Standard Specification for Mortar for Unit Masonry, American Society for Testing and Materials
ASTM C511, Standard Specification for Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes, American Society for Testing and Materials
ASTM C780, Method for Preconstruction and Construction Evaluation of Mortars for Masonry, American Society for Testing and Materials
UBC Standard No. 24-19, Specification for Mortar Cement, International Conference of Building Officials
UBC Standard No. 24-30, Standard Test Method for Flexural Bond Strength of Mortar Cement, International Conference of Building Officials
*Replaces TEK 107 © 1979 "Laboratory and Field Testing of Mortar and Grout," which has been discontinued.
NATIONAL CONCRETE MASONRY ASSOCIATION
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