Structual engineering concepts applied to products Probability-based design and test loads for ladders

Abstract

Abstract Structural engineering is based increasingly on probabilistic concepts. For building structures this approach is laid down in the Euro-codes. The idea is that the level of safety should be quantified in terms of the probability of failure. Basically, three parameters are used: – acceptable probability of failure; – loads acting on the structure ( – statistical distribution); strength of the structure (statistical distribution). The structure should be designed in such a way that the probability of failure following from the statistical distribution of the loads and strength is less than the acceptable one. For practical purposes this procedure is translated into a metod based on design values for loads and strength. This latter method is normally included in Codes. In this paper, how to start with a probabilistic approach and how to arrive at design loads is demonstrated for ladders. Design and test loads are derived on the basis of a probability of failure of approximately 1 in 1000 during the l...