Denis Albert Chamberlain

Performance of Pore-Lining Impregnants in Concrete Protection by Unidirectional Salt-Ponding Test

Until recently, solvent-based forms of monomeric alkyl (isobutyl) trialkoxy silane, produced under various trade names, were exclusively used in the United Kingdom for concrete protection of transportation structures and other structures subject to surface salt contamination. Reflecting the move toward more sustainable construction and with increasing demand for less-hazardous materials, alternative protective treatments that are based on various aqueous formulations have emerged. These treatments include dual-purpose materials for protection and concrete coloration. At the same time, developments in nanomaterials have resulted in the availability of a low-hazard pure silane that is neither water nor solvent based. This investigation evaluated the performance of this material and three water-based materials with respect to their resistance to water and salt solution absorption and chloride ion penetration. A comparative investigation assessed the possibility of using convenient concrete cubes rather than larger-scale slabs for chloride contamination testing by the salt-ponding method. The results of the study are particularly relevant to older reinforced concrete structures, which frequently suffer low concrete cover to their steel-reinforcing bars.

Remediation and Protection of Masonry Structures with Crystallising Moisture Blocking Treatment

Purpose The purpose of this paper is to investigate the performance of new and innovative crystallising materials, so-called moisture blockers, in protecting masonry structures from water ingress. Design/methodology/approach Two masonry wells were constructed; one with lime mortar and the other with cement based mortar in order to hold water inside, and then a moisture blocking product was applied at dry and wet conditions to the negative hydrostatic pressure side. The moisture levels of both, the surfaces and the substrate, were then observed for 14 days. Findings Results demonstrated that moisture blocking materials are effective methods in reducing the levels of surface moisture for bricks, mortar-brick interface and mortar. Originality/value Moisture blockers use the available water in the masonry to block the passage of water to the surface of the masonry, filling pores, cracks and spaces at the interface between mortar and bricks. This approach will deliver a wider understanding of how water-based m...