A probabilistic creep and fatigue model for timber materials

Publication KoFa03

Authors

Jochen Köhler and Michael H. Faber

Abstract

Taking basis in a fracture mechanical modeling of the development of damage in structural timber the present paper addresses the adoption of this model for the probabilistic assessment of the Duration of Load (DOL) effect in structural timber. Whereas the previously developed probabilistic models for the assessment of damage in timber structures subject to random time varying loads have been limited to consider creep effects the present model also considers fatigue induced damage. First a reformulation of the fracture mechanical model is undertaken allowing for a load controlled rather than a damage controlled lifetime prediction. A probabilistic framework is then presented on the use of the developed model in reliability analysis for the evaluation of duration of load adjustment factors kmod commonly applied in load and resistance factor design (LRFD) codes. Finally an example is considered where the use of the model is illustrated and compared with previously developed models

Published in/by

Proceedings ICASP9, 9th International Conference on Applications of Statistics and Probability in Civil Engineering, Vol. 2, San Francisco, USA, July 6-9, 2003, pp. 1141-1148.