Investigating stress distribution of crimped SMA fibers during pullout behavior using experimental testing and a finite element model

Abstract

This work enabled better understanding of crimped fiber’s pullout behavior and investigated the cross-sectional and longitudinal stress distribution, including embedded portions and free portions. A finite-element model in ABAQUS software was used to investigate the stress distribution of crimped fibers. The peak stresses of crimped fibers are at the concave bellies of crimped waves, whereas the peak stresses in the mortar matrix are at the convex sides of the waves. In a cross-section of the embedded portion, the elements were tensioned and compressed repeatedly, while in a cross-section of the free portion, the elements were only tensioned. The maximal stress in both portions was at the elements at the upper or lower of the crimped waves. In the embedded portion, the compressive stress and tensile stress at the odd and even summit waves were linear functions of the distance from the summit points to the embedded portion’s end. In the free portion, the stress was distributed unevenly along the wavelength; thus, the pullout stress varied along the free length of crimped fiber depending on the chosen point.