Standard Specification for Mortar for Unit Masonry

Includes all amendments and changes through Editorial Change 1, July 2019

Published by ASTM International, 05/01/2019


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ASTM C270, Revision 19A – Standard Specification for Mortar for Unit Masonry

This specification covers mortars for use in the construction of non-reinforced and reinforced unit masonry structures. Four types of mortar are covered in each of two alternative specifications: (1) proportion specifications and (2) property specifications.

NOTE 1—When the property specification is used to qualify masonry mortars, the testing agency performing the test methods should be evaluated in accordance with Practice C1093.

The proportion or property specifications shall govern as specified.

When neither proportion or property specifications are specified, the proportion specifications shall govern, unless data are presented to and accepted by the specifier to show that mortar meets the requirements of the property specifications.

This standard is not a specification to determine mortar strengths through field testing (see Section 3).

The text of this specification references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.

The terms used in this specification are identified in Terminologies C1180 and C1232.

The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

The following safety hazards caveat pertains only to the test methods section of this specification: 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.

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.

General Product Information:

Revision Revision 19A
Document Type PDF
Document Language English
Pages 14
Publisher ASTM International (ASTM)
Status Current

ASTM Volume

04.05: Chemical-resistant Nonmetallic Materials; Vitrified Clay Pipe; Concrete Pipe; Fiber-reinforced Cement Products; Mortars And Grouts; Masonry; Precast Concrete

Includes standards on mortar and grout for masonry construction and manufactured masonry units. Volume 04.05 also features specifications for concrete pipe, joints, manholes, vitrified clay pipe, clay drain tile, fiber-reinforced cement products, and precast concrete products.