Experimental research has pointed out that fibre reinforcement gives valuable
contribution for the shear strength of concrete beams. To obtain data to check the
validity of the formulation proposed by RILEM TC 162-TDF for the evaluation of the
fibres contribution for the concrete shear strength, sets of concrete beams were tested
experimentally. To simulate the behaviour of this kind of structures, a computational
code was developed, based on the finite element techniques. An accurate simulation of
the behaviour of structures failing in a brittle mode, such is the case of the beams failing
in shear, is a true challenge in the computational mechanics domain. To reproduce with
enough accuracy the fracturing process of this type of elements, a multifixed crack
model is implemented. The ability of the post-cracking stress-strain diagram proposed by
RILEM TC 162-TDF to simulate the crack propagation is checked. A strain softening
trilinear diagram is also derived from inverse analysis using the force-deflection
relationship obtained in RILEM three-point notched beam tests. Its capability to model
the fracture mode I is also assessed. The numerical strategy developed is described in the
present work and the appropriateness of the model is evaluated simulating some beams
tested experimentally.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BSAB/291/2002-POCTI.
Fundo Social Europeu (FSE) -SFRH/BSAB/291/2002-POCTI