: Used to determine the "Swell Pressure" (the pressure required to maintain constant volume) and the "Free Swell" (the strain under a nominal pressure).
The standard typically outlines three distinct methods (Methods A, B, and C) to simulate different field conditions: Astm D4546-21 Pdf
is the standard test method for measuring the one-dimensional swell or settlement potential of cohesive soils. : Used to determine the "Swell Pressure" (the