Influence of Concrete Strength Probability Distribution on Safety Margin of Concrete Cross-section Subjected to Shear

The subject of the work was the assessment of the safety margin of concrete cross-section subjected to shear. The assessment was performed with use of the assumptions and models taken from the two Polish standards: formerly valid PN-84/B-03264 and currently valid PN-EN-1992-1-1:2008. The goal of the performed analysis was the assessment of the influence of the probability distribution type of the concrete strength on the level of the safety margin. Two types of concrete distribution was used: normal and lognormal. On the basis of the results it was stated that values of partial security exponent ΔR show clear differences in the level of safety margin due to the distribution of strength of concrete only for models of shear resistance due to the concrete tension and that the distribution type of concrete strength affects the skewness of the shear resistance distribution in most cases.