Engineers Australia

Strength improvement of Coode Island Silt by the soil mixing method

Abdelmalek Bouazza, Asadul Haque, Pek Soon Kwan and Gary Chapman


This paper investigates the effectiveness of using soil mixing technology via cement stabilisation of locally found soft silty clay, Coode Island Silt (CIS), by studying the improvement of the strength of the treated soils. Tests were carried out in two stages, a laboratory based stabilization of the silty clay and a small scale model mixing. The improvement in terms of strength was assessed using the commonly accepted unconfined compressive strength (UCS) test. A smallscaled model mixing was set up to mimic the actual mixing scenario on sites. Although it may not be perfect, it gives an indication on the effectiveness of the cement slurry when combining with the silty clay.