Corrosion-induced cracking in LC3 and OPC mortars: influence of binder type and mechanical properties

Journal article, 2026

Limestone calcined clay cement (LC³) is a promising low- CO₂ alternative to ordinary Portland cement (OPC), but its long-term performance with respect to corrosion-induced cracking in reinforced concrete remains poorly understood. This study investigates the interplay between binder type, material properties, and corrosion-induced cracking in steel-reinforced mortars made with OPC and LC³. Accelerated corrosion experiments were conducted using the impressed current technique, and the time-to-cracking was determined from electrical potential measurements to assess the corrosion level leading to matrix cracking. LC³ mortars exhibited cracking at lower corrosion levels compared with OPC mortars, indicating a lower resistance to corrosion-induced mechanical stresses. This behavior could be correlated to fracture energy, which was lower in the LC³ systems. Although LC³ mortars showed superior resistance to chloride ingress, their reduced fracture performance suggests a potential trade-off. These findings highlight that durability assessments may benefit from considering both transport and fracture-related properties.