What are the waterproof and protective applications of polyurea in high-speed rail? Detailed introduction and answer

Spray polyurea technology is a material technology developed abroad. In the past decade, foreign scientists have successively developed a series of low pollution or even pollution-free spray technologies, such as high solid coatings, water-based coatings, radiation curing coatings, powder coatings, etc. Spray polyurea materials, as newly developed waterproof materials, have a series of advantages, such as solvent-free, pollution-free, pure green, and so on. This article will conduct a detailed analysis of the usage characteristics of spray polyurea materials and analyze their usage methods by describing their application in high-speed rail.

Advantages of spraying polyurea materials: The advantage of spraying polyurea materials is that they have good elasticity. Because of this, it is very suitable as a protective material for ground concrete. As is well known, concrete materials are very prone to cracking and have poor durability at extreme temperatures, while they are prone to cracking under severe cold or heat conditions. Polyurea materials make up for this disadvantage of concrete and have excellent crack elongation. In many cases, concrete is prone to cracking due to pressure, while the polyurea material that protects the outside does not cause any cracking. Instead, it firmly gathers the fragments of concrete. It is precisely due to the flexibility and high mechanical strength of the polyurea material that it can prevent concrete from cracking in any harsh weather, providing excellent waterproofing and protection. The second is the excellent physical properties of polyurea, such as its tensile strength, tear resistance, elongation, wear resistance, etc. Among these characteristics, high tensile strength can make the polyurea material resist the thermal expansion hazards caused by sudden changes in temperature, while good elongation will make it have a strong ability to open and close joints. If the concrete breaks or cracks under some special circumstances, Polyurea materials will automatically bridge cracks to prevent accidents caused by cracks. Furthermore, there are relatively detailed features, such as the absence of catalysts, which can quickly solidify, and can be sprayed onto any curved or vertical surface without external conditions. After spraying, there will be no sagging phenomenon, and it can also solve the problem of difficult construction in corners such as bumps and corners; Polyurea materials also have strong anti-corrosion properties, which can resist the erosion of a series of corrosive media such as acid, alkali, salt, and seawater. Significantly reduced construction time. Polyurea materials are not sensitive to moisture and moisture, which effectively improves work efficiency.

The specific application of polyurea materials in high-speed rail. It is necessary to carry out foundation treatment for the high-speed railway bridge deck. Before applying spray polyurea waterproofing technology to the high-speed railway bridge deck, it is necessary to perform shot blasting treatment on the sprayed surface, and the concrete base surface after shot blasting treatment also has certain specifications. Generally, the effective wound surface of the base surface needs to be greater than 95%, and the roughness reaches sp3 level. The second is the construction process of polyurea spraying, which requires certain spraying skills. This requires construction personnel to have considerable experience and skills, and the difficulty can be imagined. Otherwise, it will cause excessive thickness, waste a large amount of materials, and unintentionally increase the cost of spraying.