: A series of at least four identical specimens are loaded to different vertical stresses and then wetted.
ASTM D4546-21 defines laboratory test methods (A, B, and C) to measure one-dimensional swell or collapse in expansive or collapsible soils by simulating moisture changes. The standard sets technical specifications, including minimum sample sizes of 50 mm diameter and 20 mm height, and provides essential data for mitigating foundation risk. Access the standard's technical details at GlobalSpec . astm d454621 pdf