CONDITION FOR STRAIN-HARDENING IN ECC UNIAXIAL TEST SPECIMEN

Abstract

This paper discusses the adequateness of the steady state flat crackcriterion for crack propagation in Engineered Cementitious Composites.The investigation is performed by use of a semi-analytical modelas well as a Finite Element Model. The simulations are for one crackpropagating in finite and infinite sheets under uniaxial tension.The crack is assumed to be cohesive and the cohesive law appliedtakes into account fiber as well as mortar properties. It is shownthat the maximum crack opening observed during crack propagationin various test specimen geometries is small, 20 m and also smallcompared to typical deformations at peak bridging stress. The requirementof a minimum complementary energy for the fiber bridging curve isfound not to be relevant in the aim of controlling the crack openingduring crack propagation.