ABSTRACT
In the elasto-plastic fracture (EPF) model for uncracked concrete, the sources of nonlinearity can generally be classified into continuum fracture and plasticity. Continuum fracture is defined as the elasticity damage caused by dispersed defects with no clear localization [1]. This principally results in a reduced absorbing capacity of the elastic strain energy as damages accumulate. Plasticity is defined as the unrecoverable deformation of concrete after all loads are removed. In general, continuum fracture affects ultimate strength while plasticity influences deformation of concrete. The concept of combined elasto-plasticity and fracturing, which has been developed for two-dimensional concrete panels [1], will now be extended to three dimension. A schematic outline of an elasto-plasticity and fracturing system is illustrated in Figure 9.1. Concrete is idealized as a set of infinitesimal elastoplastic components. Elasticity is modeled by parallel springs while plasticity is modeled by serially connected sliders.
