Our Limerick laboratory runs a full shaker stack of 200 mm diameter sieves, from 75 mm down to the 75-micron pan, coupled with a calibrated 151H hydrometer for the fines fraction. The procedure follows ASTM D422 and D6913 protocols, which matter here because of the Shannon Estuary alluvium and glacial tills that dominate Limerick's subsurface. We dry the sample overnight at 105°C in a digitally controlled oven, then split it with a riffler to obtain a representative mass before the mechanical shaking begins. The hydrometer side uses a 1000 mL sedimentation cylinder with dispersing agent, and we log temperature and meniscus corrections at each reading interval. For clients needing a complete ground model, we often pair this with in-situ permeability testing when the silt content exceeds 35%.
A single hydrometer reading at 24 hours tells you more about settlement potential than a dozen SPT blows.
