Mechanical behavior of bio-aggregates based buildings materials

This Technical Letter examines the mechanical behaviour of bio-aggregate building materials (BBM), focusing on their performance under compressive, flexural and shear loading. The study synthesises the findings of various RILEM technical committees and recent research, highlighting the unique properties of BBM compared to conventional concrete. The paper discusses the factors influencing the mechanical behaviour of BBM, including bioaggregate type, volume fraction, morphology, mineral matrix, mix design, casting process and curing conditions. It presents detailed analyses of the BBM response under different loading conditions, highlighting the different phases observed during testing. The use of Digital Image Correlation (DIC) as an advanced measurement tool to capture BBM deformation is explored, providing insights into the heterogeneity and local behaviour of the material. The importance of the Interface Transition Zone (ITZ) between bio-aggregates and matrix is highlighted, with a focus on its formation and impact on mechanical properties. The paper also outlines the perspectives of a new technical committee aimed at harmonising test procedures and developing scientific data analysis methods for BBM. This comprehensive review provides valuable insights for researchers and practitioners working with bio-based building materials, paving the way for improved understanding and standardisation of the mechanical characterisation of BBM.