ASTM C531-18 PDF Download

ASTM C531-18 is a standard test method that focuses on measuring the linear shrinkage and coefficient of thermal expansion of chemical-resistant mortars, grouts, monolithic surfacings, and polymer concretes. The test method provides a means of comparing the relative linear shrinkage and coefficient of thermal expansion between different materials.

In this test method, the material to be tested is placed in a mold while it is in a fluid or plastic state. As the material transitions to a solid state, it adheres to and captures the end studs. The linear shrinkage is then measured by determining the change in length that occurs after the material has become rigid and strong enough to move the studs.

This test method is useful for research purposes as it provides information on the linear changes that occur in the test materials during setting and curing. However, it is important to note that other dimensional changes may also occur that are not manifested as changes in length.

It is worth mentioning that this test method is limited to materials with aggregate size of 0.25 inches (6 mm) or less. Additionally, it is not suitable for determining the overall linear shrinkage of sulfur mortars.