Numerical simulations of concrete specimens with the gradient-enhanced Eikonal non-local damage model

Abstract

Accurately predicting the response of structures subjected to complex loadings is a challenging task in civil engineering. In particular, studying cracking nucleation and propagation is essential to assess structural performances.
Quasi-brittle materials, such as concrete, are generally modeled using strain-softening constitutive models. According to the Continuum Damage Mechanics (CDM) approach, material degradation is represented at a macroscopic level by a scalar or tensorial damage variable. However, the strong localization of the mechanical fields leads to mesh-dependent finite numerical simulations.
To recover the objectivity of the results, damage models need to be regularized. Numerous techniques have been proposed (e.g., phase-field formulations, micromorphic medium, etc.), acting as localization limiters. This work concentrates on one class of regularization methods: the so-called non-local damage models of gradient type. This paper applies the eikonal gradient-enhanced model to the simulation of a few concrete specimens. The structural response and the damage maps are then compared to the experimental results taken from the literature.