Numerical modelling of steel fibers pull-out from cementitious matrixes

The improvements of cementitious matrixes due to fibers addition are directly related to fibers’ pull-out mechanism and hence the proper simulation of this phenomenon is essential for the numerical simulation of fiber reinforced cementitious composites behavior. A steel fiber pull-out model is proposed in this paper. The model takes into account the matrix properties, the fibers shape, properties and orientation and uses parameters that can be obtained from pull-out tests of straight fibers. The paper includes calibration with experimental results, application examples and comparison with other experimental results that show the ability of the model to reproduce steel fibers pull-out behavior from different types of concrete matrix. The variation of the model parameters with concrete type and strength and fiber type and geometry is also included. It is shown that the model is able to describe not only fibers pull-out process but also matrix and fibers failure for different fiber geometries and orientations.