Effect of hydrated lime on efflorescence formation
International Journal of Building Pathology and Adaptation
ISSN: 2398-4708
Article publication date: 30 April 2021
Issue publication date: 6 December 2022
Abstract
Purpose
Efflorescence formation is very common in cement-based materials. In the case of mortar, efflorescence is more studied when only Portland cement is used as a binder. However, the repair of historical heritage, as well as the construction system of some countries, usually uses mortars composed of hydrated lime and Portland cement. This study aims to determine the influence of the hydrated lime content on the incidence of efflorescence in mortars.
Design/methodology/approach
Mortars with 0%, 50%, and 100% lime/cement ratio were studied, using three different methods to accelerate efflorescence formation. The surface area of mortars affected by efflorescence was quantified by analysis using image software. Also, analysis of mercury intrusion porosity test, flexural tensile, compressive strength, absorption of water by capillarity, porosity, XRD and TGA was performed.
Findings
More efflorescence in mortars with a higher amount of lime in their composition was observed. The results show that the increase in the lime content reduces the flexural tensile and the compressive strength and increased the absorption of water by capillarity and the porosity of the mortars. The material formed by the efflorescence was calcium carbonate, proven by microstructural tests.
Originality/value
The results of greater efflorescence formation in mortars with lime are important to alert users who apply this type of material. Some type of protection must be done more rigorously for lime-cement mortars, especially concerning contact with water, since efflorescence tends to be faster for this type of material.
Keywords
Acknowledgements
This work was supported by the Brazilian Federal Agency for the Support and Evaluation of Graduate Education (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES), the National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico and Tecnológico - CNPQ) and the Araucária Foundation. The authors also thank the Federal University of Parana.
Citation
de Bem, D.H., Trentin, P.O. and Medeiros-Junior, R.A. (2022), "Effect of hydrated lime on efflorescence formation", International Journal of Building Pathology and Adaptation, Vol. 40 No. 5, pp. 775-790. https://doi.org/10.1108/IJBPA-11-2020-0102
Publisher
:Emerald Publishing Limited
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