The washed, dry aggregate sample is separated into a series of particle size fractions (e.g., 3/8" to 3/4"). Each fraction is submerged in a saturated solution of sodium or magnesium sulfate (depending upon project specifications) for 16-18 hours. The fractions are then dried to constant weight. The process is then repeated for the specified number of cycles (per project specifications). The fractions are then washed, dried and weighed. The percent loss is then reported.
Typically, about 4 kg, but determined from aggregate size and gradation
Soundness, Sodium, Sulfate, Magnesium, Durability