Reliability of the Weibull analysis of the strength of construction materials

The breaking force during transversal loading of fibre-cement corrugated roofing sheets was measured on several test samples from a serial production. The results were statistically analyzed assuming the 2-parameter Weibull statistics. In addition, Monte Carlo statistical simulations were made by using a computerised built-in random-number generator. While smaller sample data groups, mostly containing up to 50 samples, were studied in the literature, we extended their size up to 400 samples. We showed that some trends in the evaluation of statistical parameters which hold for smaller data groups, apply well to larger data groups. In particular, we confirmed that the statistical distribution of the Weibull parameters obtained from repeated Monte Carlo simulations is log-normal. Furthermore, we considered the influence of the measurement uncertainty on the statistical parameters.