Bio-stabilized modular rammed earth blocks for sustainable and aesthetic construction

Purpose This study aims to address critical limitations in rammed earth (RE) construction through a novel modular block system integrating computational design, modular construction and bio-stabilization techniques. The research quantifies environmental benefits and structural performance, establishing empirical foundations for commercial implementation of prefabricated earthen construction technologies. Design/methodology/approach The methodology used non-uniform rational B-splines (NURBS)-based parametric design for customized free-form blocks with five distinct types facilitating staggered assembly. Bio-stabilization was evaluated using animal glue and xanthan gum versus unstabilized variants. Life cycle assessment was conducted following ISO 14040 protocols. Full-scale prototyping validated manufacturing through CNC-milled formwork, while experimental validation included 28-day compressive strength testing and environmental impact quantification. Findings Full-scale prototyping confirmed technical feasibility of the modular free-form RE block system, achieving consistent production through precision CNC-milled formwork. Staggered assembly methodology enhanced structural stability via embedded reinforcement channels. Animal glue bio-stabilization demonstrated superior performance metrics (6.86 MPa strength, 38.61 kg CO2-eq/m³ emissions) compared to xanthan gum (5.58 MPa, 60.12 kg CO2-eq/m³) and unstabilized variants (1.74 MPa, 12.32 kg CO2-eq/m³). Originality/value This research pioneers computational design integration with traditional RE construction, establishing novel methodological frameworks for sustainable building. The synthesis of NURBS parametric geometry, prefabrication protocols and bio-stabilization represents significant advancement in earthen architecture, providing construction professionals with validated methodologies for achieving architectural sophistication while maintaining environmental sustainability.