Modelling and Simulation of the Strength Properties of Ultra-High Performance Fiber Reinforced Concrete Specimens

The strength performance of UHPFRC with micro and hooked-ends steel fibers was studied in this paper using Finite Element (FE) modelling and simulation. The specimens were modelled in geometry, material, constraints, load and boundary conditions using ABAQUS package and dynamic explicit analysis was used to to investigate the crack pattern, failure mode and stress-stain behaviour of the UHPFRC specimens when subjected to uniaxial compression and tension loading. Results from the FE simulation revealed that the surfaces of the UHPFRC specimens were still in good shape after attaining their ultimate resistance against compression and tension loading. The UHPFRC’s ultimate compressive strength of 260N/mm2 was just 7% higher than the experimental compressive strength. The UHPFRC exhibited both linear compressive stress-strain behaviour up to 89% of its peak strength and non-linear stress-strain behaviour with strain hardening and strain softening phases. Further findings also showed that the UHPFRC despite having ultra-high tensile strength did not undergo strain hardening phase as the vertical direction stresses were mainly distributed around the loaded section of the specimen. The FE UHPFRC models’ strength in compression and tension only has slight and negligible variations from the experimental strengths. The deformation and strength performance of the FE specimens are in perfect agreement with the experimental specimens. Therefore, FE modelling and simulation can be used as a reliable method of carrying out extensive studies on UHPFRC properties and performances.