A Review of the Structure, Application, Production Process and Effect of Additives in Traditional Gypsum Mortar

Mortars are an integral part in the construction of historical and even modern buildings. They are used in different parts of the building, such as mortar between bricks and stones, floor mortar, surface coating mortar and other parts of the building, so it is used to create a quality and stable building. Over time, efforts should be made to improve the quality of mortars and materials. The properties of gypsum mortars are influenced by the three main factors of mine type, baking method and the use of additives. For this reason, the purpose of this research is to investigate these factors. The results of the studies showed that in different mines and even different parts of the same mine, it is effective in creating differences in the properties of gypsum mortar; For example, in different mines, due to the conditions of the mine, such as the pressure on the gypsum crystals or the presence of impurities in the mine, crystals with different characteristics will be created. How to burn and prepare gypsum is also effective in determining the properties of these types of mortars. For example, baking gypsum at a temperature of 120 to 180 degrees Celsius will produce beta hemihydrate gypsum. Additives also affect the properties of plaster in different parts, which can include resistance effects (compressive, tensile and abrasion resistance), setting time and resistance to moisture; For example, it is magnesium oxide and aluminosilicates, each of which increases the compressive strength and setting time in plaster mortar.