Estimating of measurement uncertainty of tensile strength test for deformed steel bars for concrete reinforcement

The purpose of this study was to estimate the measurement uncertainty for deformed steel bars for concrete reinforcement. The material investigated were deformed steel bars produced by 2 manufacturers, which each consisted of 7 diameters. The tensile strength of the specimens measured through static tensile testing was used for estimating the measurement uncertainty. The interested part in the research is that the testing of deformed concrete steel which is due to the formation of uneven surface, the cross-sectional area shall not be measured by measuring the diameter but using the nominal diameter stated by the manufacturer. In this analysis, the measurement uncertainty was estimated using a larger number of samples. The results can be very useful to the laboratory to know the limitation of the testing machine in determining the characteristics of different deformed steel bars. The investigations also show the scatter of the test results.