Internal and external factors affect the life of stone

I. Overview
People tend to think that Stone is a long-term high-grade decorative materials, decorative stone can be used once and for all. In actual fact, in the natural environment, dust, exhaust, acid rain, ice and other pollutants on the stone used in buildings is very likely to fade, pollution or damage, greatly reduces the life of the stone and decorative effect, while errors due to construction methods, can also cause the failure of decorative stone, which had in the short term re-building renovation, resulting in substantial waste of manpower and resources.
To produce a variety of stone disease and shorten the life of many reasons, mainly summed up in professional terms: First, internal reasons: both the structure and chemical composition of the stone caused the change; the second is an external cause: both mining and processing methods, installation and construction technology, use of the environment and other factors.
Second, the impact of life of stone and produce the main stone disease
Common stone diseases are: water spots quit, salting salt on Bai Hua, vomiting yellow rust, frost damage, surface corrosion, pigment pollution (including oil), powder of moss growth and spalling. To produce a variety of stone disease and shorten the service life of reasons, summarized in two aspects: First, internal reasons, that is, the structure of the stone structure and chemical composition caused by changes; the second is external factors: the mining and processing methods, installation construction techniques and the use of environmental and other factors.
1, from the stone within reason
(1) stone texture and structure: the existence of natural stone in both the micro-cracks and pores, the adsorption constant, daily would be fine in the air of dust and dirt, as capillary action and slowly infiltrated into the stone house, which greatly reduces the decorative stone performance and service life. The smaller the pore, capillary action and surface adsorption is stronger.
(2) the relatively complex chemical composition: some of the stone components is easy with the external environment play a role, so that the phenomenon of stone or variations generated erosion. Stone generally contain iron in varying degrees the composition, by tidal erosion will produce rust yellow. The higher iron content in the stone, rust Huang Yuerong easy to produce. In addition, most of the main component of natural marble carbonate, such as calcium carbonate and magnesium carbonate, there is a small amount of alkaline oxides. Calcium carbonate and magnesium carbonate is a relatively stable compound, but some of the basic oxides chemically unstable, in a wet environment, easy with the acid in the air as carbon dioxide, sulfur dioxide, oxides of sulfur trioxide ﹑ ﹑ dioxide nitrogen, a chemical reaction changes the physical structure of the marble interior. Similar chemical damage will occur on the other stone, the light will dull the stone surface, and even the color Fading, there scar; severe decrease in hardness of natural stone make the surface weathering.

2, because from the outside stone
Decorative effect of the stone and the external life of many reasons, such as mining and processing, storage and transportation process of improper maintenance, installation of stone materials used for bonding the impact and natural environmental factors.
(1) mining, processing and storage processes: like the crack of stone mining methods may be related to inappropriate; processing of iron tools used in stone may have to stay hidden yellow rust, improper coolant may be contaminated stone Stone; improper maintenance during storage and transportation, but also will produce rust and straw yellow stone and other pollution.
(2) Installation of process and bonding materials: If you install the stone used in the wet cement paste paste method construction, the cement of the alkaline soluble material erosion due to rainwater seeping into pores along the stone surface, while alkaline compounds such as Ca (OH) 2 with CO2 and H2O in the air a chemical reaction of CaCO3 crystals in the stone surface, the formation of salt on the phenomenon of salting. In addition, because after the formation of some of the cement hydration salts are hygroscopic and will absorb into the stone in the air after the water surface of the water in the stone plaque, seriously affect the appearance. In addition, improper use of the paste materials, such as gum paste some stone, the stone may also have yellowing.
(3) environmental factors: environmental factors include pollution, acid rain and frozen destruction. Natural environment, air pollution, acid rain and other pollutants are man-made pollution and corrosion of the stone. In addition, freezing damage is also an environmental factor can not be ignored, because the stone has a water absorption (even if the construction is the use of hanging stone), in the cold winter, because of ice and accelerate the weathering process and reduce its strength, not only affect the use life, but also a threat to personal safety.