Numerical Simulation and Structural Evaluation of Earthen Masonry Systems Built with Optimized Granite-Lime Stabilized Compressed Earth Blocks

Abstract

This study adopts a combined experimental and numerical finite element research design to evaluate the structural performance and engineering characteristics of Compressed Earth Blocks (CEBs) stabilized with industrial Granite Waste Powder (GWP, 0–15%) and hydrated lime (0–6%). Rapid urban growth and the high carbon footprint of Portland cement necessitate sustainable, low-carbon structural alternatives for affordable housing. An experimental design evaluating 13 mix formulations was assessed for geotechnical characteristics, mechanical strength, capillary absorption, and surface abrasion resistance according to African Regional Standards (ARS 674–677). Subsequently, a finite element analysis (FEA) framework was developed in ETABS to simulate linear static displacement and nonlinear pushover response under service and wind loading combinations. Laboratory results demonstrated that the ternary mix containing 15% GWP and 6% lime (Mix M4) yielded a peak dry bulk density of 2120 kg/m3 at 90 days. Mix M4 achieved a 28-day compressive strength of 5.22 MN/m2, representing a 108.8% increase over the 28-day control (2.50 MN/m2), and reached 6.50 MN/m2 at 90 days, reflecting a 124.1% increase over the 90-day control (2.90 MN/m2) and a 24.5% strength gain from 28 to 90 days. Stabilization significantly enhanced durability, reducing capillary water absorption to 0.68% and abrasion loss to 0.58%. Structural simulations revealed a strong numerical-experimental correlation (R2 = 0.92), with optimized blocks achieving up to a 65% reduction in maximum story displacement and a transition to high lateral stiffness. The findings validate GWP-lime stabilized CEBs as a structurally sound, environmentally resilient masonry system suitable for load-bearing affordable housing applications.