1. The role of lower plants

Under suitable conditions of water and temperature, sporangia of mosses, fungi and other organic substances attach to the surface of stone, and begin to grow, which makes the surface of stone form various organic stains. These organic substances, in order to survive, compete with carbon dioxide, sulfur dioxide, nitrogen dioxide and other substances in the air, change the stone. Surface texture structure of wood. In addition, these plants form organic acids with water after death, which accelerates the ageing of stone and causes denudation of stone.

2. ultraviolet radiation

Stone itself has many capillary holes, and the smaller the capillary, the more obvious the capillary phenomenon. Therefore, after absorbing water, under the radiation of sunlight (ultraviolet), the evaporation rate of water in the capillary pore of stone will accelerate, and the erosion rate of the material with erosion to stone will intensify, which will lead to the aging of stone.

3. visbreaking

Adhesion is one of the installation methods of stone. The residual adhesives on the stone surface relax the cementing minerals of the bonded stone due to ageing, relax the interior of the stone and easily peel off the surface, thus accelerating the ageing of the stone.

4. the role of heat energy

Stone expands due to daytime heating, and shrinks due to night cooling, which results in thermal expansion and contraction. Stone contains many different minerals with different expansion coefficients and occurs granular denudation or massive disintegration.

5. freezing and thawing of water

The freezing and thawing action of water can also make the stone weathering: the temperature drops below 00C, and the water becomes ice, which causes the rapid expansion of the ice after absorbing water and makes the stone disintegrate and break up.

Therefore, if we want to prevent the weathering of stone, we must take corresponding measures according to the physical reasons causing the weathering. Only in this way can we prevent the weathering of stone used in the construction industry.