V3I1P82

Assessment of the Mechanical Behavior of Cement–Periwinkle Shell Ash Stabilized Lateritic Soils Using Experimental Testing and MATLAB Analysis

Timothy Omotoyosi Awanu^1*

Abstract

The need for sustainable and cost-effective soil stabilization methods has led to increased interest in utilizing agro-industrial wastes. `This study presents a comprehensive assessment of the mechanical behavior of lateritic soils stabilized with sustainable blends of ordinary Portland cement and Periwinkle Shell Ash (PSA). The research integrates an extensive experimental program with robust computational analysis. Systematic mix designs with varying proportions of cement (2–6%) and PSA (2–8%) were implemented to evaluate key geotechnical properties, including the California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS), and Indirect Tensile Strength (ITS). The results demonstrate that PSA-cement stabilization produces significant and consistent improvements, with unsoaked CBR values ranging from 24.6% to 78.6%, UCS from 1.2 MPa to 6.0 MPa, and ITS from 0.3 MPa to 1.5 MPa. Statistical analysis, supported by MATLAB-based visualizations including box-and-whisker, scatter, and strip plots revealed moderate variability and symmetric distributions, confirming the reliability of the stabilization process. The optimal performance was observed with a synergistic blend of 6% cement and 6% PSA, yielding peak mechanical properties. The study concludes that cement-PSA blends are a technically viable, sustainable, and effective stabilizer for lateritic soils, demonstrating considerable potential for use in subgrade and base layers for low-to-medium-volume road construction, while highlighting the utility of computational tools in geotechnical materials research.

Keywords:

Lateritic soils, Periwinkle shell ash, Soil stabilization, Compressive strength, Tensile strength, California Bearing Ratio