Hybrid adobe infill walls with industrial waste additives: Experimental characterization and seismic performance assessment

Abstract

This study investigates the enhancement of the structural performance and resilience of reinforced concrete structures through the stabilization and fiber reinforcement of adobe masonry, aimed at use as sustainable infill walls in reinforced concrete frames. By combining paper and pulp recycling (PPR) fibers and biomass bottom ash (BBA) as additives, we produced hybrid adobe materials whose mechanical (compressive and flexural strength) and thermal properties were characterized experimentally. Finite element models of multi-story reinforced concrete frames incorporating these materials as infill panels were then developed, using nonlinear static pushover and dynamic time-history analyses to assess seismic performance under near-fault ground motions. Results show that moderate additions of PPR and BBA (10-15%) can significantly increase compressive strength and stiffness, while PPR fibers improve ductility and energy dissipation by controlling crack propagation. Conversely, excessive BBA contents may reduce ductility due to higher porosity. The study demonstrates that optimized hybrid adobe infill walls can improve lateral load capacity and reduce seismic displacements, offering a balanced trade-off between stiffness and ductility. These findings support the integration of industrial wastebased materials into performance-based and resilience-based design frameworks, contributing to the development of modern, sustainable, and modular structural systems with enhanced multi-hazard resilience.