Abstract
This study investigates the integration of robotic additive manufacturing (RAM) and structural topology optimization to develop high-performance earthen walls for arid rural housing in Morocco. Traditional rammed earth and adobe architectures offer excellent thermal mass but suffer from structural vulnerability under seismic loads and labor-intensive construction processes. To address these challenges, we propose a computational design-to-fabrication workflow that optimizes the internal macro-porosity of 3D-printed clay-based mixtures. By applying density-based topology optimization, we designed wall components that minimize material use while maximizing structural stiffness and thermal resistance. Locally sourced Moroccan clays were characterized and amended with agricultural waste (barley straw fibers) to optimize rheology and printability. Experimental testing of the printed prototypes demonstrated a 34% reduction in material consumption, a 42% improvement in compressive strength compared to traditional adobe, and a significant enhancement in thermal insulation properties, reducing thermal conductivity to 0.32 W/m·K. Numerical simulations of a representative rural housing unit in the Draa-Tafilalet region showed that the optimized earthen walls could maintain indoor thermal comfort for 82% of the summer season without active cooling. These findings demonstrate the viability of combining digital fabrication with vernacular materials to deliver sustainable, resilient, and affordable housing solutions in arid regions.
