Round-robin analysis of the RILEM TC 162-TDF beam-bending test:: Part 1 -: Test method evaluation

A round robin test programme was carried out on the beam-bending test recommended by the RILEM TC 162-TDF [1]. Plain concrete and steel fibre reinforced concrete (SFRC) beams were included in the test programme, The material variables for the SFRC beams consisted of two concrete strengths, three fibre dosages and three types of Fibres. A comprehensive statistical analysis was carried out to determine the applicability and robustness of the test method. It was found that although inter-lab variations do occur, this was relatively small compared to the inherent material variation. It is also possible that the high variations observed could be due to the relatively small cross sections used for the test beams. Additionally, an investigation was carried out to evaluate the objectiveness of the calculation procedure proposed by RILEM TC 162-TDF to obtain the necessary design parameters. It was found that the prescribed calculation procedure was satisfactory, as the variation between the design parameters calculated at different laboratories was generally within the range of +/-5%. An alternative method of obtaining the design parameters, by considering residual strengths, is suggested as it simplifies the calculation procedure and the test method. In general, the beam test was found to be a good robust test and relatively easy to carry out..