clay-based poultices, building materials, desalination
Abstract
One of the major threats affecting the lifetime of cultural monuments and residential buildings are the water-soluble salts raising the necessity for desalination activities.In the following paper three clay-based compositions have been studied by varying ratio of binder (clay) to filler (sand and cellulose) as follows: clay to sand mass ratio 1:2, 1:5 and clay/sand/cellulose mass ratio of 1:4,5:0,5.The experimental examination of desalination compositions included determination of density, drying shrinkage, pore size distribution using mercury porosimetry before and after exposure to the solutions of water soluble salts.In order to control desalination process quantitative and qualitative analysis of ions of soluble salts (distribution profiles of nitrate, chloride and sulphate ions as well as crystalline phases of the samples by using chemical and XRD analysis) in both material – poultice, as well as salinated building material have been performed.The obtained results have shown that the main parameter determining salt transport mechanisms and desalination efficiency is pore size distribution of the substrate and poultice as well as nature and ratio of the binder and filler.Obtained experimental data can be used for further research as well as planning of practical restoration activities in environments with high concentration of water-soluble salts.
