Evaluating Corrosion Damage Evolution of Cement Mortar in Acid Environment via Relative Elasticity Modulus Method

Abstract

In order to study the damage variation along thickness from surface, a relative method combined with impulse excitation test was studied in this work to evaluate the elastic modulus of cement mortar corrosion damage layer, by simulating the damage layer as a coating. The damage layer with different damage degree is treated as multilayer coatings in which each layer has different properties. The elastic modulus of each layer is determined by using the relative method step by step. Single face of Portland cement mortar specimens was exposed in an aggressive environment, with 0%, 5%, 7.5% and 10% HCl content, respectively. The corrosion damage degree and evolution law of the mortar were investigated by measuring the elastic modulus of surface damage layer. With the increase of HCl concentration, thickness of corrosion damage layer increased and the modulus of the damage layer decreased greatly. The elastic modulus of each corrosion layer was obtained at different depths. By this way, damage depth and damage evolution were evaluated effectively.