Abstract
This paper attempts to quantify the strain response over time of samples of unloaded concrete block masonry observed in the laboratory with respect to the environmental variables of temperature and relative humidity. The notion of a thermo-hygral inertia is introduced, as deviations from the expected pattern of strain are considered over the experimental time scale in whole and in part. A method is elucidated which allows correction of the observed strain for non-constant ambient conditions, and the implications of the findings are considered in terms of likely effects on the use of laboratory test data on the monitoring of real structures.
Résumé
Cet article décrit une méthode pour la mesure en laboratoire de la déformation d'échantillons de bloc en béton non-chargé, en fonction du temps et de deux variables d'environment: la temperature et l'humidité relative. La notion d'une inertie hygro-thermique est introduite, tandis que les écarts par rapport aux types de déformations prévues sont considérés pour l'ensemble de la durée de l'essai en totalité et en partie. Une méthode est développée pour corriger la déformation observée selon les variables ambiantes. Puis, ces résultats sont discutés en termes d'effets probables sur l'utilisation de données provenant des essais en laboratoire et sur le contrôle des structures réelles.
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Editorial note Dr. T. G. Hughes is a RILEM Senior Member and a member of TC MMM on Computer Modelling of Mechanical behaviour of Masonry Structures.
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Hughes, T.G., Harvey, R.J. Environmental influences on the shrinkage of concrete block masonry. Mat. Struct. 30, 225–232 (1997). https://doi.org/10.1007/BF02486180
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DOI: https://doi.org/10.1007/BF02486180