Performance of novel 3D approach with explicit definition of fibres-concrete interaction in predicting the FRC/FRHPC response

The motivation for this study is a new material design for wave energy convertor floater hull, which requires exceptional performance in harsh marine environment under extreme weather conditions.Fibre reinforced concrete (FRC) utilises its highest performance after initial cracking, exhibiting strain-hardening when the cracks bridged by fibres redistribute the stresses over larger volume of concrete and thus increase the load bearing capacity of the specimen.The proper numerical description of cracks is of major importance to obtain physically meaningful results for high performance concrete (HPC) reinforced with alternative reinforcements like short fibres or textile reinforcement.Thus, the goal is to introduce the numerical tool in order to investigate the behaviour of FRC and FRHPC members.Since, such tool can be calibrated for a given type of fibres, then for any new concrete mixes, if only the properties of plain concrete are known, one can easily estimates the influence of steel fibres additive without necessity to proceed additional series of experiments.The main idea of presented approach is to assume the fully 3D modelling with taking into account explicitly the distribution and orientation of the steel -fibres embedded in 3D concrete continuum.Moreover, an explicit bond-slip interaction between each fibre and concrete is implemented.Consequently, different failure modes associated with fibres pull -out or fibres rupture can be independently simulated.As a benchmark, results obtained from experimental campaign on different specimens made from concrete with steel fibres of different sizes and dosages were taken.Results of numerical simulations were directly compared with experimental outcomes in order to validate and calibrate FE-model and to introduce the efficient numerical modelling tool.