Rapid tests for the detection of chlorides in RC structures: State-of-the-art and first experimental findings

The assessment of chloride ions' presence and quantity within the cementitious matrix is of utmost importance in evaluating the deterioration status of existing reinforced concrete (RC) structures. This parameter is closely related to the potential for severe and localised corrosion attack of the reinforcing steel bars. The presence of chlorides in RC structures is commonly attributed to proximity to marine environments or the use of de-icing salts on infrastructure, although for structures dating back to the 1960s-70s, chloride presence can also be traced to contaminated raw materials or the use of calcium chloride-based accelerators during construction. However, the adoption of rapid on-site tests for detecting chlorides in concrete remains limited in professional practice. This article offers a concise overview of available techniques and presents preliminary findings from an ongoing experimental campaign. The campaign aims to compare and evaluate the reliability of various slightly destructive rapid tests conducted on concrete samples with known chloride concentrations