Materials and Structures

, Volume 37, Issue 3, pp 177–183 | Cite as

Shrinkage and creep of masonry mortar

  • J. J. Brooks
  • B. H. Abu Bakar
Article

Abstract

Shrinkage and creep results are presented for different types of masonry mortars having a wide range of strength. The range of values implies that the type of mortar has an appreciable influence on deformation of masonry. The results are analysed, together with other data obtained from other investigations carried out over several years in the same laboratory, and predictive models developed. Factors quantified are strength, volume/surface/ ratio, time of exposure to drying (shrinkage) and time under load (creep). While creep is unaffected, for a given strength, shrinkage of water-cured mortar is greater than shrinkage of mortar that is cured under polythene. When based on 28-day strength, the average error of prediction for shrinkage is 19% but if based on the strength at the start of shrinkage, the error coefficient is reduced slightly to 16%. Creep is estimated with an average error of 24%.

Keywords

Shrinkage Pier Mortar Joint Error Coefficient Cube Strength 

Résumé

Les résultats de retrait et de fluage sont présentés pour différents types de mortiers de maçonnerie ayant une large gamme de résistances. Le type de mortier aurait ainsi une influence négligeable sur la déformation des maçonneries. Les résultats sont ensuite analysés; d'autres données ont été obtenues conjointement à partir d'autres études effectuées pendant plusieurs années dans le même laboratoire et des modèles prédictifs ont été développés. Les facteurs qui ont été quantifiés sont la résistance, le rapport volume/surface, le temps de séchage (retrait) et le temps sous charge (fluage). Alors que le fluage n'est pas affecté, pour une résistance donnée, le retrait du mortier exempt d'eau est plus important que le retrait du mortier exempt d'humidité sous polyéthylène. Lorsque la résistance est fixée à 28 jours, l'erreur moyenne de prévision du retrait est de 19% mais si elle est mesurée en début de retrait, l'erreur est légèrement améliorée (16%). Le fluage est estimé avec une erreur moyenne de 24%.

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Copyright information

© RILEM 2004

Authors and Affiliations

  • J. J. Brooks
    • 1
  • B. H. Abu Bakar
    • 2
  1. 1.University of LeedsUK
  2. 2.Universiti Sains MalaysiaMalaysia

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