The drying shrinkage of mortar as determined by this test method is a measure of the decrease in length of test specimens under controlled drying conditions, after an initial period of moist curing.

Since test specimens are not completely unrestrained during the initial period of moist curing, measurements of drying shrinkage by this test method are most useful for comparative purposes rather than as absolute values.

The drying shrinkage of unrestrained laboratory tested mortar samples is different from that experienced in a masonry wall where influences include restraint, masonry unit absorption, ambient temperature and humidity, thickness of joint, length of continuous wall, etc.

1. Scope

1.1 This test method covers the measurement of unrestrained drying shrinkage of masonry mortars.

1.2 This test method is applicable to Specification C 270 Type N, Type S, and Type M mortars under the property or proportion specifications. Due to the tendency to damage lower strength specimens during demolding, it is not applicable to lower strength mortars, such as Type O mortars.

1.3 This test method is intended for research purposes only.

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

1.5 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 and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens)

C157/C157M Test Method for Length Change of Hardened Hydraulic-Cement Mortar and Concrete

C270 Specification for Mortar for Unit Masonry

C305 Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic Consistency

C490 Practice for Use of Apparatus for the Determination of Length Change of Hardened Cement Paste, Mortar, and Concrete

C511 Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes

C778 Specification for Sand

Keywords

drying shrinkage; masonry; mortar; unrestrained; Drying shrinkage; Masonry mortar and grout; Shrinkage--drying;

ICS Code

ICS Number Code 91.100.10 (Cement. Gypsum. Lime. Mortar)

Citing ASTM Standards

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