Politeknik Dergisi, pp.1, 2021 (ESCI)
Analysis of size effect phenomenon in quasi-brittle materials is
presented in this research using damage plasticity model. Notched and
unnotched specimens under three-point bending fracture test are analyzed
by setting a 3D finite element model. For this purpose, Abaqus software
is utilized. Concrete damage-plasticity model (CDPM) enhanced with
crack band approach is used to conduct simulations of concrete
specimens. The efficiency of this model is investigated especially for
size effect phenomenon. 2D finite element model is setup for three-point
bending beams in order to estimate fracture parameters for specific
span to depth ratio, L/D=2.176. The simulations are conducted for each
different notch depths. 8-node quadratic plane stress elements are used
to define 2D domain and singularity field at the notch tip is modeled
using quarter point technique. Energy release rate is calculated using
J-integral approach. Obtained results are compared to experimental ones
reported in literature and are also compared to the Bazant’s size effect
law. This study shows that concrete damage-plasticity model enhanced
with crack band approach can capture size effect observed in
concrete-like materials’ fracture.