Abstract
For structures that do not have a high sensitivity to creep or for preliminary design of any structures, practising engineers demand a short formula for predicting the material creep properties. Such a formula is given in the present addendum to a previous six-part paper. It is based on optimal fitting of the previously published log-double power law to the formulae of the BP-KX model. A simple formula giving directly the compliance function rate is also presented. Finally, a simple method of improving the predictions on the basis of short-time measurements is described, and tables giving the statistics of the deviations of the prediction formulas of the simplified model and its short form from the data in the literature are presented.
Resume
Dans le cas de structures qui ne montrent pas une forte sensibilité au fluage, ou bien pour le calcul préliminaire de quelques structures que ce soient, les ingénieurs ont besoin d'une formulation simplifiée qui leur permette d'anticiper les propriétés de fluage du matériau. Le complément qu'on donne ici à l'article en six parties précédemment publié propose cette formulation qui repose sur un ajustement optimal de la loi de double puissance logarithmique que l'on connaît déjà aux formules du modèle BP-KX. Une formule simple pour la vitesse de la compliance est aussi présentée. Finalement, on décrit une méthode simple pour améliorer la prévision à longue durée à partir de mesures de courte durée et on donne les statistiques des erreurs des formules présentées.
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Bažant, Z.P., Xi, Y. & Baweja, S. Improved prediction model for time-dependent deformations of concrete: Part 7—Short form of BP-KX model, statistics and extrapolation of short-time data. Materials and Structures 26, 567–574 (1993). https://doi.org/10.1007/BF02472831
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DOI: https://doi.org/10.1007/BF02472831