Numerical modeling of fiber pull-out micromechanics in concrete matrix composites

The presented research work compares numerical results of single fiber pull-out of elastic matrix with the experimental data obtained for single steel fiber pulled out of highstrength concrete matrix. The pull-out process was studied by means of accurate 2D elastic and 3D elasto-plastic finite element models taking into account the nonlinearity. Numerical modeling was performed for straight-shaped fiber embedded into the elastic matrix under variable angle with respect to applied pulling force and at variable depth. Friction between fiber and matrix, matrix shrinkage as well as elastic and plastic deformations in the fiber were taken into account. The objective of numerical modeling was to evaluate significance of different phenomena such as friction between steel fiber and concrete matrix, matrix shrinkage and fiber plasticity in a single fiber pull-out process by taking into consideration experimental findings.