ASTM C531 – Standard Test Method for Linear Shrinkage and Coefficient of Thermal Expansion of Chemical-Resistant Mortars, Grouts, Monolithic Surfacings, and Polymer Concretes
Description:
Significance and Use
4.1 This test method offers a means of comparing the relative linear shrinkage and coefficient of thermal expansion.
4.1.1 The material to be tested is placed in the mold in a fluid or plastic state. As the material makes a transition to a solid state, it adheres to and captures the end studs.
4.1.2 The linear shrinkage measured is the change in length that occurs after the material is rigid enough and strong enough to move the studs.
4.2 This test method can be used for research purposes to provide information on linear changes taking place in the test materials. Other dimensional changes may occur that do not manifest themselves as changes in length.
Scope
1.1 This test method covers the measurement of the linear shrinkage during setting and curing and the coefficient of thermal expansion of chemical-resistant mortars, grouts, monolithic surfacings, and polymer concretes.
1.2 A bar of square cross-section is cast to a prescribed length in a mold that holds measuring studs that are captured in the ends of the finished casting.
1.2.1 The change in length after curing is measured and used to calculate shrinkage.
NOTE 1: Shrinkage determinations should not be made on sulfur mortars, since this test method cannot truly reflect the overall linear shrinkage of a sulfur mortar.
1.2.2 The change in length at a specific elevated temperature is measured and used to calculate the coefficient of thermal expansion.
1.3 This test method is limited to materials with aggregate size of 0.25 in. (6 mm) or less.
1.4 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.
ASTM C522