Diffusion of chlorides in cracked strain-hardening cement-based composites (SHCC)

Abstract

Strain-hardening cement-based composites (SHCC) are high-performance fiber-reinforced composites with promising durability properties due to their considerably enhanced crack control under tensile load conditions. The knowledge of the transport properties of such composites in cracked state are crucial for estimating their durability characteristics. In the project at hand, chloride diffusion tests were performed and their results were related to crack widths and crack distances in SHCC specimens under investigation. SHCC specimens were first subjected to uniaxial tension under deformation-controlled loading regime in order to achieve formation of multiple cracks. Optical investigations provided a basis for evaluating the crack pattern. Eventually the cracked specimens were exposed to chloride solutions. Qualitative and quantitative chloride evaluations were conducted and discussed with particular respect to the recorded crack pattern. The results obtained within the project for chloride diffusion in cracked and crack-free areas enlarge the basis for assessing durability characteristics of SHCC and for further developing existing durability concepts and approaches.