Title: Mathematical Modeling Of Strength Properties In Psa-Cement Stabilized Lateritic Soils Using Scheffe's Mix Model
Authors: Timothy Omotoyosi Awanu, Damini Righteous Gilbert
Volume: 10
Issue: 2
Pages: 96-101
Publication Date: 2026/02/28
Abstract:
This study developed and validated mathematical models to predict key strength parameters compressive strength, tensile strength, and brittleness index of lateritic soils stabilized with periwinkle shell ash (PSA) and cement. Using Scheffe's simplex mix design and Osadebe's regression principle, polynomial equations were derived from systematically varied proportions of PSA, cement, and water. Statistical validation via F-test and Rē analysis confirmed high model accuracy and predictive reliability. The compressive strength model achieved an Rē of 0.994, the tensile strength model an Rē of 0.98, and the brittleness index model an Rē of 0.892, all with F-values below the critical threshold, confirming adequacy at a 5% significance level. Results indicate that PSA significantly enhances the mechanical properties of lateritic soil, with optimal performance observed at 15% PSA content. The inclusion of PSA not only increased compressive and tensile strength but also reduced the brittleness index, indicating improved ductility. These models provide an efficient tool for optimizing sustainable, cement-partial replacement mixes in geotechnical applications, supporting both economical and environmentally conscious construction practices.