STOCHASTIC ANALYSIS OF STEEL STRUCTURES .

In this paper two methods suitable for the stochastic analysis of steel structures are described and investigated: the Monte Carlo method, arranged into several variants, and the linearization method. The methods are applied for two important structural systems, namely for a truss and for a fixed-end frame with four bars. Elastic behaviour of the steel structure is expected, i. e. the calculated limit state occurs when the equivalent stress reaches the yield point in tension. The internal forces are determined through the finite elements method adapted for linear elements. As basic criterion the coefficient of utilization of the cross section chi equals sigma //s//r/ sigma //y has been selected (ratio between the tension calculated and the yield point). This coefficient provides the required information on the relation between the load and resistance of the steel structure; it represents the level of its reliability, and at the same time its degree of economy.