Validation of a stochastically homogenized peridynamic model for quasi-static fracture in concrete

Abstract

Concrete is the most widely used man-made composite material. Its damage and fracture behavior determines reliability of many engineering structures. The quasi-static fracture behavior in concrete structures is investigated here using an intermediately homogenized peridynamic (IH-PD) model. The case of anchor pull-out from a concrete plate is used to validate the IH-PD in terms of the load–displacement behavior (peak load and softening behavior), crack path asymmetry and path tortuosity. While the simplest material constitutive relationship (linear elastic with brittle failure) is used for the peridynamic bonds, the IH-PD model is shown to be superior in modeling concrete failure than a corresponding homogenous PD model with a material model (bond force-strain relationship) with softening. The model is successfully tested for additional cases pertaining to mode I, mode II dominated, and mixed mode fracture. The model’s success comes from the preservation of some micro-scale heterogeneity, stochastically generated in the IH-PD model to match concrete’s phases volume fractions, while its computational cost is equivalent to that of a homogenized peridynamic model.