Abstract
The complexity of the full BP-KX model for creep and shrinkage prediction presented in the previous five parts is due to the large number of influencing factors taken into consideration rather than an inherent complexity of the theory. However, a sophisticated model with all these factors is needed only for the design of special structures, such as bridges of a record span, buildings of a record height, or nuclear reactor structures. For most practical applications, many of the factors can be eliminated and can be fixed at their typical values. This yields a simplified BP-KX model which is presented in this last part. The simplified model should suffice for many practical applications and is suitable for standard code-type recommendations of engineering societies. The design of every structure can begin with this simplified model, and only if the effects of creep and shrinkage are found rather significant is analysis according to the full BP-KX model necessary.
Resume
On doit attribuer la complexité du modèle intégral BP-KX pour la prédiction du fluage et retrait du béton présenté dans les cinq chapîtres précédents au grand nombre de facteur déterminants pris en considération plutôt qu'à une complexité inhérente à la théorie. Cependant, un modèle sophistiqué comportant tous ces facteurs est nécessaire seulement pour le calcul des structures telles que des ponts de très grande portée, des bâtiments de très grande hauteur ou des réacteurs nucléaires. Dans la plupart des applications pratiques, de nombreux facteurs peuvent être éliminés et fixés à leurs valeurs typiques, ce qui donne un modèle BP-KX simplifié que nous présentons dans cette dernière partie. Le modèle devrait suffire pour de nombreuses applications pratiques et convient pour les recommendations à usage de code ou de norme dans l'industrie. On peut commencer le calcul de n'importe quelle structure à l'aide de ce modèle simplifié et, seulement si l'effet du fluage ou du retrait paraît assez marqué, recourir à l'analyse selon le modèle intégral BP-KP.
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References
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Bažant, Z.P., Panula, L., Kim, JK. et al. Improved prediction model for time-dependent deformations of concrete: Part 6—Simplified code-type formulation. Materials and Structures 25, 219–223 (1992). https://doi.org/10.1007/BF02473066
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DOI: https://doi.org/10.1007/BF02473066