Comparison of continuous and discontinuous constitutive models to simulate concrete behaviour under mixed‐mode failure conditions

Abstract

SUMMARYThe paper presents detailed FE simulation results of concrete elements under mixed-mode failure conditions according to the so-called shear-tension test by Nooru-Mohamed, characterized by curved cracks. A continuous and discontinuous numerical two-dimensional approach was used. In order to describe the concrete's behaviour within continuum mechanics, two different constitutive models were used. First, an elasto-plastic model with isotropic hardening and softening was assumed. In a compression regime, a Drucker-Prager criterion with a non-associated flow rule was used. In turn, in a tensile regime, a Rankine criterion with an associated flow rule was adopted. Second, an isotropic damage constitutive model was applied with a single scalar damage parameter and different definitions of the equivalent strain. Both constitutive laws were enriched by a characteristic length of micro-structure to capture properly strain localization. As an alternative approach, the extended finite element method was used. Our results were compared with the experimental ones and with results of other FE simulations reported in the literature.

Discrete element method simulations of fracture in concrete under uniaxial compression based on its real internal structure

“…The non-smooth edges of cracks interact with each other by creating the so-called interlocking effect (Eliáŝ and Stang, 2012; Scholtès and Donzé, 2013; Walraven, 1981). Fracture greatly affects strength of quasi-brittle materials (Bobinski and Tejchman, 2016a, 2016b) and therefore its understanding is vital for a reliable engineering design and construction of building infrastructure. The experiments and numerical simulations evidently show that the macroscopic concrete behaviour greatly depends on properties of its meso-components (aggregate volume, aggregate size, aggregate roughness, aggregate stiffness, particle size distribution curve, mortar volume and macroporosity).…”

Construction of Discrete Element Constitutive Relationship and Simulation of Fracture Performance of Quasi-Brittle Materials

“…In addition, the damage parameters in the normal and shear directions are assumed to have the same value in the model. This indicates that there is just one scalar damage parameter ( ), which is commonly accepted in quasi-brittle material modeling [ 34 , 35 , 36 ].…”

Mesoscale numerical study of aggregate size in concrete by discrete element method

“…The damage parameter in normal and shear directions have the same value. It means that there is only one damage parameter ( f D ), which is widely accepted in quasi-brittle materials modelling [14][15]. ,…”