Application of Gypsum and Fly Ash as Additives in Stabilization of Tropical Peat Soil

The demand for land in conjunction to infrastructure development is become crucial and expensive. In the near future, a problematic soil such as peat is becoming a final alternative. This study aimed to investigate effect of fly ash and gypsum on the mechanical properties of peat soil. The results showed that soil treated with mixture of 10% Fly Ash (FA) and Synthetic Gypsum (SG) indicated lower liquid limit values than the SG treated soil. In compaction tests, the maximum dry density of both increased in both SG treated soil and FA-SG treated soil. The permeability of SG treated soil increased with the increases in SG contents. Similarly, occurred to permeability of FA-SG treated soil however, its values are lower than the soil treated without FA. Shear strength of SG treated showed decreased with increasing amount of SG content. In contrast, the FA-SG treated soil exhibited higher strength if compared to that of SG treated soil.