Test methods used to characterize steel fibre reinforced concrete (SFRC) at the material constitutive level continue to be a topic of discussion in the scientific community. The principal aim of these tests, as is required for input into physical models…
Test methods used to characterize steel fibre reinforced concrete (SFRC) at the material constitutive level continue to be a topic of discussion in the scientific community. The principal aim of these tests, as is required for input into physical models to describe structural behaviour, is to gather the residual or post-cracking response of the SFRC. Typically, this response is derived following an inverse analysis of flexural prism tests. However, it has been suggested that the anisotropy of the material due to the dispersion and orientation of the fibres cannot be accounted for in these tests. Multiaxial double punch tests have been proposed to overcome these issues. However, to the authors’ knowledge, no attempt has been made to quantify the size effect in this test set-up, nor to study whether a sufficiently high amount of fibres can mitigate this effect. To this end, this paper presents preliminary findings on an experimental campaign investigating the size effect in multiaxial double punch tests on SFRC cubes. In this investigation, the specimen size 3 3 3 varied from 75 to 600 mm , covering a range of approximately 5 to 40 times the maximum aggregate size (D = 16 mm). The supplied fibre dosages ranged from 0-1% by vol. It is found max that there was a pronounced size effect with respect to the cracking load of the cubes, which appears to be in good agreement with theoretical predictions. Further examinations are currently being carried out to quantify the size effect in the post-cracking phase of the tested SFRC specimens.