Evaluation of carbonate precipitation methods for improving the strength of peat soil

Abstract

This research was carried out to evaluate the potential improvement of the strength of peat soil with the carbonate precipitation method. The grouting solution’s optimum combination was determined and mixed to soil sample with a various density of 1.15, 1.20, and 1.25 g/cm3. The mass of precipitated carbonate within the soil and its effect on peat soil’s increasing strength was evaluated by the unconfined compression (UCS) test. The mass of precipitated carbonate within peat soil was evaluated by acid leaching method, respectively. The UCS test showed that the strength of treated peat soil had improved significantly. The treatment using carbonate precipitation brings about an improvement of 38% to 48% compared to the untreated sample. The maximum strength of 375.12 kPa was achieved at a density of 1.25 g/cm3. The result of this study also indicated that the initial density has no significant impact on the improvement of precipitated carbonate in peat soil. A relatively similar precipitated carbonate of 2-3% of soil mass was formed in the entire soil sample. This study elucidated that the carbonate precipitation method is a potential method to improve the peat soil’s shear strength.