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Abstract
Consolidants are used widely in stone sculptures, statues and building units to improve the cohesion between the grains, increase mechanical strength and thereby improve the material durability. Although they are widely used in conservation projects, their performance in brick masonry, especially under salt weathering conditions, demands further research. This study aims to study the behaviour of brick-lime mortar masonry systems under accelerated salt weathering after consolidation with tetraethoxysilane (TEOS). Mass loss monitoring, mineralogical characterisation and microstructural analysis were performed to evaluate the alterations in the substrates, which are influenced by the salt type, crystallisation mechanism, consolidant composition and substrate mineralogy. The weathered brick-mortar sandwiches were sheared to understand the role played by consolidants on the mechanical performance of the composite system. The results indicate that TEOS strengthened the bricks and mortars both individually and as composites, with a risk of altering the pore structure.
References
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