Proc. of the 7th Int. RILEM Symp. on Fibre Reinforced Concrete: Design and Applications (BEFIB2008) pages:173-182
7th Int. RILEM Symp. on Fibre Reinforced Concrete: Design and Applications (BEFIB2008) location:Chennai date:17-19 September 2008
The postcracking tensile strength of fibre reinforced concrete must be determined experimentally. Best known test methods are the 3-point bending test (EN 14651:2005), the uniaxial tension test, the 4-point bending test and the wedge splitting test. All these test methods show a large scatter on the test results which is due to the non-uniform fibre distribution and the rather small cracked area in the specimen.
As a result, one of the possible solutions to avoid this large scatter is to increase the cracked area. This can be achieved by using the round panel test (ASTM C1550-05). Indeed, from round panel tests it has been found that the variation on its test results decreases with almost 50% with regard to those obtained by means of the above mentioned tests.
The research described in the paper examines the feasibility of a reduction of the dimensions of the round panel without loosing the small scatter. The investigated parameters are: diameter of the panel, thickness of the panel, fibre type (steel – synthetic) and fibre quantity.
At this time a lot of design recommendations for fibre concrete are based on the 3-point bending test. For this reason, the link between the results of the round panel test and those of the 3-point bending test has been analysed in this research.