Fuzzy reliability of concrete bridge elements with respect to the reinforcement chloride corrosion

摘要

The complex problem of assessing the reliability of a reinforced concrete structure exposed to the reinforcement chloride corrosion taking into account two type of uncertainty, namely the randomness and fuzziness of structure as well as load and corrosion parameters is considered. An original algorithm for evaluating the reliability of beam and beam-plate reinforced concrete bridges is presented. Many arbitrary simplifications are assumed and for this reason the limit condition is described by a fuzzy number and the ion-propagation time by a fuzzy random variable. The most important element of the elaborated algorithm is considering the problem in two separate time periods: in the period of the ion propagation through the concrete cover and in the period after the initiation of the reinforcement corrosion. Such approach leads to an integral expression for calculating the probability of failure. The theoretical considerations are illustrated by a numerical example.