Rubber powder modified Asphalt (AR)
It in heavy handed in with scrap tire rubber powder and asphalt admixtures, under the joint action of rubber powder by absorbing asphalt in the resin, hydrocarbons and other organic matter, after a series of physical and chemical change, make the powder wet, expansion, viscosity increases, softening point, and both the rubber and asphalt viscosity, toughness and elasticity, and thus improve the performance of rubber asphalt road.
"Rubber powder modified asphalt" refers to make waste tires into rubber powder, as modified agent added to the matrix asphalt, in a dedicated special equipment, through the high temperature, additives and shear mixing and a series of adhesive material made of.
The modification principle of rubber powder modified asphalt is the modified asphalt cementing material which is formed by the full blown expansion reaction of the tire rubber powder in the high temperature condition. Rubber powder modified asphalt has great improvement on the performance of matrix asphalt, and is superior to the modified asphalt made by the commonly used modifier SBS, SBR and EVA. Due to its excellent performance and great contribution to environmental protection, some experts predict that rubber powder modified asphalt could replace SBS modified asphalt.
Rubber powder can be added to asphalt in construction of highways and highways. This kind of application is not used as a way to consume waste tires at first, but to improve the performance of asphalt to achieve similar performance with high quality asphalt containing new elastomer. The advantages of adding gelatine to asphalt include reducing the tendency of pavement cracking (especially in cold regions), and improving the durability, water resistance and stability of rocks. Rubber modified bitumen is more durable, with an average life span of seven years longer than traditional asphalt mixtures.
Used in modified asphalt rubber is a polymer with high elasticity, in vulcanized rubber powder is added to the matrix asphalt, can achieve even more than styrene - butadiene - styrene block copolymer modified asphalt the same effect. The characteristics of the modified asphalt include:
1. The penetration of the needle decreases, the softening point increases, and the viscosity increases, indicating that the high temperature stability of the asphalt improves, and the rutting and pushing of the road surface in the summer are improved.
2. Lower temperature sensitivity. When the temperature is low, the asphalt becomes brittle and the pavement stresses crack. When the temperature is high, the road becomes soft and is deformed by the loading of the vehicle. And with the rubber powder modified asphalt heat of improved, resistance to improve liquidity, rubber powder modified asphalt viscosity coefficient is greater than the matrix asphalt, description of the modified asphalt have higher flow resistance to deformation ability.
3. The low temperature performance was improved. Rubber powder can increase the low temperature delay of asphalt and increase the flexibility of asphalt.
4. Adhesion enhancement. Due to the increase of the rubber asphalt film thickness, the asphalt pavement can improve the water resistance and prolong the life of the road.
5. Reduce noise pollution.
6. Increase the grip of vehicle tires and road surface, improve driving safety.