Distributed cracking and stiffness degradation in fabric-cement composites: Fid-Bau Portal

Distributed cracking and stiffness degradation in fabric-cement composites

Mobasher, Barzin / Peled, Alva / Pahilajani, Jitendra

Abstract Formation of distributed cracking and the associated degradation in the stiffness of fabric-cement composites under tensile loading were studied. Composites made from low modulus woven polyethylene fabric and bonded Alkali Resistant (AR) glass mesh were manufactured by means of pultrusion technique. The influence of fabric type, matrix modification and curing as well as the pressure applied after pultrusion were studied using tensile stress strain response. Three distinct measures of damage including quantitative crack spacing by image analysis, stiffness degradation, and microstructural observation by optical and scanning electron microscopy are evaluated. The evolution of crack spacing as a function of applied strain was correlated with the tensile response as well as with the stiffness degradation for various composites. Also, the microstructure of the different composites was characterized and correlated with their mechanical properties using optical and scanning electron microscopy. It was observed that the mechanical properties as well as crack spacing and composite stiffness were significantly affected by the matrix formulation, curing procedure, and the intensity of the pressure applied after the pultrusion process. The best tensile performance was achieved for glass fabric composites with a high content of fly ash.