The influence of oiled fiber, freeze-thawing cycle, and sulfate attack on strain hardening cement-based composites

Abstract

Abstract The interfacial transition zone (ITZ) between the fiber and the matrix significantly influences the strengthening and toughening effect of the fiber for the matrix. The ITZ between the fiber and mortar is a weak link in strain hardening cementitious composites (SHCC), the loose structure is easily damaged, and it is the main channel of ion attack. The oil reduces the hydrophilicity of fiber and the bonding strength of fiber and mortar, which decreases flexural and compressive strengths, but increases the tensile ductility. The compressive strength increased with the increase in the microhardness of ITZ. Both freeze-thawing cycle and sulfate attack reduce the flexural and compressive strengths, and ductility of SHCC. The failure of ITZ is responsible for the performance decrease. The strength of the samples containing oiled fiber after the freeze-thawing cycle and sulfate attack decreases more significantly.