RASH Manual RASH Manual | Page 17

Assessing aggregate strength Pour distilled water into small dishes or a paint pallet on a flat stable surface. 1 3 Place the aggregates carefully into the water and leave for 10 minutes. Observe how much slaking and dispersion has occurred at the 10 minute point. Use the photos below to help assess strength and stability. 4 Get three soil aggregates from the soil sample. They need to be around 3-5mm in size. Air dry for 24 hours first if possible. 2 Scoring the aggregate strength The Aggregate Strength Score has two parts – for slaking and dispersion. Score results using the table below: Slaking results More than 70% slaked 20 to 70% slaked Slight slaking around edges No slaking Dispersion results Strong dispersion. Completely cloudy Moderate dispersion Partly cloudy around aggregate No dispersion Scoring guide Poor Moderate Good Very good Score 0 1 2 3 RASH MANUAL - 17