The source of salt and alkali on stone surface and the formation of salt and alkali spots

1. The basic ingredients in the cement, such as sodium hydroxide, potassium hydroxide, sodium carbonate, etc.), due to various reasons (such as water, clean water, ground water, groundwater), made the cement in the stone and stone under wet stick after be affected with damp be affected with damp, caused by moisture to evaporate on the outward, the alkaline composition in cement by stone material microporous or juncture, along with the capillary action to the stone material surface,Forming patterned saline spots;

2. Some marble itself contains alkaline components (such as some beige-colored marble), in the humid air even if there is no wet paste installation, will also be due to water migration of their own precipitation of salt, salt spots;

3 in some saline areas, soluble salt and alkali (such as sodium sulfate, and sodium carbonate, etc.) will migrate upward along the wall base with water, in the building on the wall foot part of the stone surface precipitation;

4. In coastal areas, as the sea breeze blows the seawater mist to the land shore, the sea salt (such as sodium chloride) will precipitate on the stone surface of the exterior wall of the building, and also form white saline spots;

5. In China, with the annual rainy season from the south to the north (such as Hainan, the Pearl River Delta south wind days, the Yangtze River Delta plum rain season, north of the Qinling Mountains sauna days, etc.), seasonal stone salt spots gradually appear.

From the four characteristics of the stone saline-alkali spot, five sources and the formation of stone saline-alkali spot has a common characteristic: that is, there is water in the stone.Only when the water in the stone is removed, the problem of salt and alkali spots in the stone can be completely solved.