A displacement-based inverse analysis method to estimate in-situ Young's modulus of steel rust in reinforced concrete

The in-situ Young's modulus of rust is an important parameter in corrosion analyses. In this paper, the in-situ Young's modulus of rust in reinforced concrete is determined by a displacement-based inverse analysis method. The full field displacements of the surface of concrete in an accelerated corrosion test are first monitored by digital image correlation. The process of rust expansion which in turn induces concrete cracks is then modeled by using a smeared crack model. It is observed that the critical expansion displacement causing the crack of concrete surface is controlled by the mechanical properties of the materials and the geometry of the specimen but not the rate of corrosion and environmental conditions. The non-destructive testing method of rust presented in this study may also be applied to other granular materials.