Nano-mechanical properties of alkali-silica reaction (ASR) products in concrete measured by nano-indentation

Abstract

This paper presents a study on the nano-mechanical properties of alkali-silica reaction (ASR) products formed in laboratory-prepared concrete specimens. The nano-mechanical properties (elastic modulus and hardness) of the ASR products were investigated by nano-indentation, and scanning electron microscopy (SEM) was used to investigate the corresponding material phases. The combined nano-indentation and SEM analysis identified two types of ASR products with distinct morphologies and compositions: a rosette-like ASR product and a granular ASR product. The nano-mechanical properties obtained from the nano-indentation tests were correlated with the two nanostructural morphologies. The findings provide insight into the correlation between nano-mechanical properties and nanostructure and improve our fundamental understanding of the mechanical behavior and durability of ASR-affected concrete.