Evaluation of the Influence of Structural Parameters on the Mechanical Properties of Foam Glasses via In-Situ Micro-CT Mechanical Testing

Abstract

Foam glass made from waste glass has high chemical and mechanical stability and flexible structural properties, making it suitable for a wide range of applications. To ensure its reliability, it is essential to understand its mechanical properties and fracture mechanisms. In this study, we investigated morphological features related to pore structure alongside mechanical properties, specifically Young's modulus and compressive strength, of three different monolithic foam glass samples using micro-computed tomography combined with ex-situ and in-situ uniaxial compression experiments and Digital Volume Correlation (DVC) analysis. The foam glasses exhibit an inverse relationship between mechanical strength and factors such as wall thickness, porosity, pore size and irregularity, with the compressive strength following a power-law correlation with the proportion of large pores. The multi-peak behavior of the stress-strain curves indicates micro-cracking within the porous lattice. Micro-CT data show that damage is concentrated at the upper and lower extremes of the specimens, and that the applied strain induces changes in the porosity, mean pore diameter, and pore sphericity, driven by deformation and collapse of the pore structures. DVC analysis quantitatively validated these observations.