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Materials and Structures

, Volume 29, Issue 8, pp 500–505 | Cite as

Sensitivity study of BP-KX and B3 creep and shrinkage models

  • B. Teplý
  • Z. Keršner
  • D. Novák
Scientific Reports

Abstract

A numerical study of sensitivity analysis and statistical prediction of concrete creep average compliance function and shrinkage strain is presented. Two advanced models—the BP-KX and the B3—are studied. The influence of uncertainty of the basic input variables is taken into account by considering them as random variables. The statistical correlation is also treated in a simplified form for the assessment of its influence. Utilising the numerical simulation Latin Hypercube Sampling, the statistical and sensitivity analyses are performed. The results using different models are also compared. Two alternative measures of sensitivity analysis are utilised: sensitivity in terms of coefficient of variation and sensitivity in terms of nonparametric rank-order correlation coefficient. The strength of concrete and humidity appear as the most dominant factors with regard to the variability of results. Also, the estimations of distribution functions of the models are shown. They provide the possibility of establishing appropriate confidence limits. The significant difference in their ranges for the models in question is also shown.

Keywords

Shrinkage Latin Hypercube Sampling Creep Model Shrinkage Strain Complementary Distribution Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Résumé

On présente une étude numérique de l'analyse de la sensibilité et de la prévision statistique de la fonction moyenne de conformité du fluage du béton et de la déformation du retrait. Les modèles BP-KX et B3 sont étudiés. On prend en compte l'influence de l'incertitude des variables fondamentales introduites, en les considérant comme des variables aléatoires. La corrélation statistique est également traitée de manière simplifiée afin d'évaluer son influence. L'analyse statistique et celle de la sensibilité sont réalisées au moyen de la simulation numérique «Latin Hypercube Sampling». On compare les résultats obtenus avec les différents modèles. On utilise deux mesures alternatives de l'analyse de la sensibilité à partir, d'une part, de la détermination du coefficient de variation, et d'autre part, de celle du coefficient de corrélation. La résistance du béton et l'humidité apparaissent comme des facteurs dominants en ce qui concerne la variabilité des résultats. On présente également les fonctions de distribution des modèles qui permettront d'établir des limites de confiance convenables. On démontre la différence significative de leur étendue pour les modèles dont il est question.

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Copyright information

© RILEM 1996

Authors and Affiliations

  • B. Teplý
    • 1
  • Z. Keršner
    • 1
  • D. Novák
    • 1
  1. 1.Institute of Structural Mechanics, Faculty of Civil EngineeringTechnical University of BrnoBrnoCzech Republic

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