Advancements in Soft Soil Stabilization by Employing Novel Materials through Response Surface Methodology

Stabilization using industrial by-products is presently gaining importance in the construction sector for improving the geotechnical characteristics of soft soils. The optimum dosage of stabilisers has become of great interest to experimenters in terms of improved strength, time, and economy for construction projects. This work presents the utilization of biomedical waste ash for improving the strength of soft soil. In this paper, response surface methodology (RSM) was adopted to determine the optimum combination curing period (C) and biomedical waste ash (BA) quantity for attaining the maximum unconfined compressive strength (UCS) of soft soil and to reduce the number of trial tests required. The response factors C and BA were varied from 0 to 14 days and 4% to 20%, respectively, and the experiments were conducted according to the experimental plan provided by the RSM design. Based on a Face-centred Central Composite Design (FCCCD), a mathematical equation was created for the experimental results. Analysis of variance (ANOVA) was used to determine the generated model’s significance, and the results indicated a statically significant model (p ≤ 0.05). The results revealed that the curing period imparts more influence towards strength improvement, and the optimum dosage was 19.912% BA, with curing of 14 days to yield a maximum UCS of 203.008 kPa. This optimization technique may be suggested to obtain a preliminary estimation of strength prior to stabilization.