The most common problem of stone cracking in winter is mainly caused by freezing and thawing. This phenomenon mainly occurs in places near the north or cold weather.
Reasons for “freezing and thawing”
The main reason for stone freezing and thawing is that when the pores of stone absorb the water, the water in stone will start to freeze once the temperature drops below 0 ° C.
Matter obeys the law of “expansion by heat and contraction by cold”, while water does the opposite. The density of water is the highest at 4 ℃, and the water molecules operate independently in the form of fluidity. When the temperature of water decreases from 4 ℃ to 0 ℃, the water molecules in the ice are arranged in a three-dimensional pattern in an unusually loose form, which leaves many “holes” and reduces the density. The experiment shows that when 1 cubic meter of water freezes, its volume will increase to 1.11 cubic meters.
Therefore, when the water enters the pores or gaps of natural stone, it will freeze when it gets cold, and the volume will increase, thus expanding the pores or gaps of natural stone. Then, the natural stone will absorb more water, and the pores or gaps will be further expanded. This vicious cycle will eventually lead to the fragmentation of natural stones.
Prevention of “freezing and thawing”
Regarding the freeze-thaw phenomenon, no matter what stone protection method, its source is the main factor that forms freeze-thaw — water. We can prevent freezing and thawing if we prevent water from entering the stone. Therefore, the freezing and thawing of stone materials should be treated in advance. The stone materials should be protected with a stone curing agent.
After the stone is dried, a protective agent such as a waterproof agent shall be applied on the surface of the stone repeatedly and evenly. The purpose is to prevent moisture from entering the pores of the stone and to completely prevent freezing and thawing.
The reason why stone protection is important is to make stones healthier and reduce or even eliminate stone pathological changes. Environmental factors are unavoidable, but we can protect the stones artificially. Stone freezing and thawing are only stone problems, but stone protection can avoid many stone problems.