Round-robin analysis of the RILEM TC 162-TDF beam-bending test: Part 3—Fibre distribution

• Published in: Materials and structures 2003-11, Vol.36 (9), p.631-635
• Main Authors: Barr, B. I. G., Lee, M. K., de Place Hansen, E. J., Dupont, D., Erdem, E., Schaerlaekens, S., Schnütgen, B., Stang, H., Vandewalle, L.
• Format: Article
• Language: English
• Subjects: Beams (structural); Building construction; Building materials; Civil engineering; Counting; Degrees of freedom; Design of experiments; Fibre; Fibres; Mathematical analysis; Robustness; Studies; Test methods
• ISSN: 1359-5997; 1871-6873
• DOI: 10.1007/BF02483283

A round robin test programme was executed amongst several laboratories on the beam test recommended by the RILEM TC 162-TDF [1]. In the proposed test method, the mid-span deflection is to be measured on both sides of the beam (referred to as δ^sub 1^ and δ^sub 2^). A systematic fibre counting exercise was carried out on several beam specimens to investigate whether there is a correlation between differences between δ^sub 1^ and δ^sub 2^ and the fibre distribution. The findings of the investigation suggest that differences between δ^sub 1^ and δ^sub 2^ are not strongly linked with the fibre distribution regardless of concrete strength. It is likely that this phenomenon arises because the supports and loading points have enough degrees of freedom to accommodate any unevenness on the specimen surface. This reflects well on the robustness of the proposed test method as it means that the proposed boundary conditions are able to adapt and tolerate (to a certain degree) surface non-uniformity. However, it is also suggested that significant differences between δ^sub 1^ and δ^sub 2^ may be brought about by experimental errors. The fibre count also reveals that toughness increases with the number of fibres across the critical section.[PUBLICATION ABSTRACT]