Permeable silane impregnating coating is a kind of waterproof coating. It was developed in 1990s in China and used widely in Concrete Anticorrosion Construction of port wharf. With the continuous development and application of silane, the application scope of silane has also evolved from the initial port terminal to the anti-corrosion of harbour engineering, traffic engineering, industrial facilities and civil buildings. Next, we will discuss and share some of the silane problems.


First of all, why can silane play the role of concrete anti-corrosion?
Concrete in open-air environment will be eroded by water and chloride ions, affecting the durability of the structure itself. In fact, water will cause many structural diseases of concrete, which is the carrier of many diseases. Therefore, waterproof measures on the surface will play a great role in the anti-corrosion of concrete. Silane is an excellent permeable impregnating agent with small molecular structure. It reacts with hydrated cement to form a polysiloxane interpenetrating network structure. Through solid chemical bonding reaction, the micro-structure of concrete surface is endowed with long-term hydrophobicity, and the function of breathing and air permeability is maintained, which greatly reduces the invasion of water and harmful chloride ions. Enter to ensure that concrete structure is free from corrosion.

Second, what is the difference between silane and other waterproof coatings?
Permeable organic silane surface protective coating is a kind of waterproof coating, which differs from other waterproof coatings in that the former uses the permeability of concrete to penetrate into a certain depth of concrete surface for impregnation protection, while the latter completely blockages the pore or closes the capillary pore on the surface. Therefore, silicone impregnation protection can not only significantly reduce the water absorption of concrete capillary, reduce chloride ion erosion, prevent freeze-thaw damage, steel corrosion and mold breeding, but also ensure long-term durability (alkali resistance, ultraviolet resistance).

Thirdly, how to ensure the anti-corrosion effect of silane to the greatest extent during construction?
The following conditions should be met: concrete age (> 28 days); concrete grade C30-C45; concrete surface is dry and clean, without obvious dirt, dust and linen; there is basically no severe weather such as rain and gale within 7 days of construction; silane dosage is weighed according to the instruction; concrete surface temperature is between 5-40 C. If the above conditions are basically met, spraying silane (liquid or paste), after 7 days of maintenance, the effect is obvious.


Fourth, the more silane is used, the better?
The amount of silane should be within the appropriate range. The excessive amount of silane will lead to the following results: first, the appearance of concrete structure will change in color, the surface will be blackened and stained, which needs to be restored in the later stage; secondly, the hydrophobic effect will become worse, and the lotus leaf effect after 7 days of maintenance will be less obvious than that of concrete with normal amount of construction.

Fifth, the lotus leaf effect of silane is not obvious, can we say that silane can not play a role in anti-corrosion?
First of all, the greatest cause of the inconspicuous effect of lotus leaf may be the construction requirements to ensure the anticorrosion effect. Secondly, "lotus leaf effect" is intuitive, but not completely credible, and not comprehensive. For example, if there is a hydrophilic coating on the surface of concrete impregnated with silane, there will be no lotus leaf effect. In this case, we should wipe off the dust on the concrete surface with a cloth or a high-pressure water gun, wait for the concrete surface to dry and see if there is lotus leaf effect. If not, we need to drill core sampling, test the depth of impregnation and confirm the impregnation effect.


Silane impregnation technology has obvious effect on improving the anti-corrosion effect of concrete. With the development of technology and the application of construction, silane will play a more and more extensive role in improving the durability of concrete and prolonging the service life of concrete structures.