Progress research on earth construction: Cast earth with glass wastes, cement kiln bypass dust and activated clay

A sandy soil was stabilized by 10% CEM I 42.5 R. Up to 50% of the cement was replaced by waste glass powder, cement kiln bypass dust or activated clay. Polynapthalene sulfonate superplasticizer was used to increase the fluidity of the mixes. The flowability is measured by means of the flow table according to ASTM C230. The compressive strengths of cubic samples are recorded. It is found that the fluidity of the soil increases with increasing the superplasticizer dosage. A 90-day strength of 6.0 N/mm2 is obtained by replacing 25 wt.% of the cement with waste glass powder using a w/b ratio of 1.5 and 2% superplasticizer. Segregation occurs with higher glass content. The use of cement dust as cement replacement material leads to lower strength values. Stabilization of the soil by 5% cement, 10% activated clay or glass powder, 5% cement dust, with 3% superplasticizer, produces castable mix with a 28d-strength of ∼20 N/mm2 when cured in water. This value decreases drastically in absence of cement.