In recent years, the online Red economy has become more and more developed. Various anchors on the network are changing patterns to increase their fans. What they are most afraid of is “losing powder”. Stone will also “lose powder”, you know? I believe many people who have been exposed to stone care understand that stone can wipe a layer of dust from the surface with one touch; Dust is nothing, and some will have small particles. What causes this phenomenon? How can we solve this problem? Then in this article, let’s talk about the “powder falling” of stone.
There are many reasons for the phenomenon of “powder falling” of decorative stones, which are analyzed one by one below
1、 Stone “powder dropping” is a process of physical weathering
Physical weathering is the phenomenon of stone damage under the action of various stresses. The most common sources of stress are:
① Salt: salt crystallizes in the pores of stone or forms hydrate in contact with water to become a solid. The volume expands, dissolves, and crystallizes repeatedly, and finally expands and breaks the pores of the stone, forming cracks and flake spalling on the surface of the stone.
② Water freezing: water freezing will produce freezing and thawing. When the temperature drops, freeze-thaw will occur, and ice will freeze inside or around the stone gap, resulting in expansion; When the temperature rises, the freeze-thaw disappears, and the stone will shrink, expand and shrink repeatedly, resulting in cracks in the stone.
③ Dry wet cycle: the stone surface may change alternately in different seasons, different meteorology, and different periods. If the stone has not been used as a protective agent, it has distinct hydrophilicity and obvious hygroscopic expansion property. The wet stone will expand (about 0.1% – 0.01%), shrink after drying, and frequent dry and wet changes will rupture the stone and accelerate the surface weathering.
④ Hot and cold cycle. When the stone surface is heated by sunlight and cooled at night, the thermal expansion and contraction of the stone will change day after day, and the stress of cold, heat, dry and wet cycles will cause stone cracks after a long time of repeated action.
2、 The “powder dropping” of stone is the result of chemical weathering
The most typical manifestation of the stone loss of light, black scale, and shelling are on marble. When stone meets acid-base solution, it will produce a chemical reaction and form relatively loose salts, resulting in surface wear, loss of gloss, and falling off of the stone. There are many sources of acid-base solutions:
① Artificial daily cleaning: in daily cleaning, acid-base detergent is used to chemically dissolve and soak the stone for a long time to accelerate the chemical weathering process of the stone. The anti-pollution ability of the weathered stone surface decreases. After cleaning in the morning, it may hide dirt in the afternoon. If it is dirty, it will be cleaned again and again, which will accelerate weathering and make it worse.
② Acid rain and acid mist: the surface of calcium-containing stone reacts with acid rain and acid mist to form calcium sulfate, which is a loose swelling substance. The specific surface area of calcium sulfate is very large, which is easy to absorb dust and form a black scale layer.
In some projects, after several years of wall paving, it is found that the wall stone is dust when touched by hand, and small particles will fall. After communication and investigation, it is found that the wall faces to the west, with floor glass windows in the West. The sun shines in the West in summer, cools at night, expands and contracts with heat, and stone weathering occurs. The solution is: first, when the project has just entered the site and the stone has not been weathered, the chemical protection of the stone should be done well, the maintenance of the stone should be done regularly, and the sun protection of the stone should be done at the same time. These works can prevent stone weathering, slow down the weathering process and prolong the service life of the stone.
But what if the stone has weathered? Through chemical protection and polishing maintenance, the stone can no longer be weathered, maintain the status quo, and the weathered stone will still lose powder. If you want to completely change this situation, you’d better do the deep renovation of stone. During the renovation process, pay attention to the chemical protection of stone materials, and those that have been weathered or seriously weathered need to be hardened.
For the weathered situation, deep renovation is needed to fundamentally solve this phenomenon. In the process of renovation, stone chemical protection should also be done. Given the weathering situation, it is necessary to harden the stone, and the overall renovation effect will be better. Finally, when polishing.
Stone weathering, in addition to natural reasons, is more the use of stone and care side did not pay attention. The user of stone has no professional knowledge of stone care and does not know how to maintain it. However, as a professional of stone care, we should always remember that any stone problem is prevention first and prevention is better than cure. Prevent the occurrence of stone lesions, maintain the decorative effect of stone, and save natural resources, which can better highlight the value of stone care.
To avoid the problem of “powder falling” of stone, the stone must be properly protected on six sides before leaving the factory. During the installation of stone, the plates that need to be re-cut must be protected before installation. Don’t panic about the “powder falling” plates. Please ask a regular stone protection company to deal with them. Well, this article will be written here first. I look forward to your email for the shortcomings email@example.com, put forward more valuable suggestions.