Influence of cracking on moisture uptake in strain-hardening cementitious composites

Strain-hardening cementitious composites (SHCCs) are a class of cement-based materials that show strain-hardening behavior in tension. This is achieved by multiple microcracking, which results in a tightly spaced crack pattern with relatively small crack widths (50-80 μm, in general) and high strain capacity (up to 4-5%). Because of their ductile behavior and tight crack widths, SHCCs are commonly used for concrete repair applications. However, because of the tight crack width and crack spacing, moisture uptake by capillary suction can take place very fast. This could result in rapid access of deleterious substances, such as chloride ions, resulting in corrosion initiation. In this study, X-ray tomography is used for monitoring and quantification of water uptake in SHCC. Specimens were first loaded to different strain levels in uniaxial tension. Then, they were subjected to a capillary suction test. The performed test was subsequently modeled using a lattice model. © 2016 American Society of Civil Engineers.