Author(s)

W. Graf, B. Möller & M. Bartzsch

Abstract

In order to analyze the load and modification process of composite structures with uncertain parameters a numerical simulation model with fuzzy parameters is developed. The uncertain input set X( , , )θ τϕ  is mapped by use of a mapping operator onto the uncertain result set Z( , , )θ τϕ . The numerical simulation is carried out with the aid of α -level-optimization. As mapping operator (deterministic fundamental solution) the geometrically and physically nonlinear analysis of plane composite/reinforced bar structures is applied. It is based on an incrementally formulated system of first order differential equations. A flexible bond in the longitudinal direction of a composite bar – e.g. a steel-concrete-composite or a concrete-concrete-composite – is included in this system of differential equations by an additional degree of freedom. The algorithms are demonstrated by way of examples. Keywords: computational methods, uncertainty, fuzzy processes, composite bar structures, system modification. 1 Introduction Concrete-steel-composites are usually considered as composite structures. They consist of a steel beam, e.g. an I-profile, which is connected by means of shear connectors to a concrete slab. The shear connection represents a flexible bond between concrete and steel. The effect of flexible bond occurs not only at concrete-steel-composites, but also at e.g. concrete-FRP-composites and most other inhomogeneous cross sections. If in case of structural upgrades an old

Keywords

computational methods, uncertainty, fuzzy processes, composite bar structures, system modification.