High Temperature Creep and Structural Fire Resistance

Abstract

Under real fire conditions, creep becomes a dominant factor and influences fire resistance of structural steel members. In this paper, the effect of high temperature creep on fire response of structural system is investigated. Phenomenological (rheological) creep models for materials with non-invariant properties are discussed here. The behavior of steel material at elevated temperatures is expressed in form of a constitutive equation. New probability-based and deterministic models describing the behavior of time-dependent materials are presented. The Gauss-Legendre method is used in order to obtain the solution of the viscoelastic integral equation. The review of literature clearly indicates that the creep effect on the structural fire response did not receive much attention. This study indicates that neglecting high temperature creep in fire resistance analysis of steel structures can lead to non-conservative predictions. The results are supported by step-by-step practical design examples and should be useful for practicing structural and fire protection engineers, code developers as well as researches and university faculty personal.