The key to stabilisation is in the proportion of binder mixed with the soil. Proportions are analysed as a percentage of dry mass. In real site conditions the proportions used, vary with different soils and other factors. ISCO specialists will provide you with guidance in each particular case. In the UK it is generally accepted that around 8% of binder is necessary to create a durable subbase or base. Your ISCO professional specialist will look at parameters such as: ·

• Compressive strength and/or Bearing Capacity.
• Stiffness as measured by a Nottingham Asphalt Tester.
• Timing of the overlay. When this is done and the extent of traffic both prior to and following the overlay.
• Compressive strength required, along with frost analysis to determine frost resistance.
• Volume stability when immersed in water. (As per BS 1924:1990 Part 2 immersion test).

The above parameters demand laboratory analysis of the soil base in most instances, and ISCO provide these analyses as part of their service. It is important that site analyses are done by an experienced professional, familiar with the measurements required. Once again, the experience of the soils engineer is vital in understanding the typical ground conditions found on site.