Asphalt concrete is generally represented by "AC", which means asphalt concrete; 13 refers to the nominal maximum particle size in mineral aggregate gradation, which is13 mm; ; AC- 13 refers to asphalt concrete with a nominal maximum particle size of13 mm.
The asphalt in AC- 13 can use ordinary asphalt or modified asphalt. Modified asphalt AC- 13 is asphalt concrete with modified asphalt, and its nominal maximum particle size is13 mm.
There are many kinds of modified asphalt, such as SBS modified asphalt, SBR modified asphalt, PE modified asphalt, etc. Recently, hot asphalt rubber is one of them.
Production method of SBS modified asphalt: using matrix asphalt as raw material, adding a certain proportion of SBS modifier, uniformly dispersing SBS in asphalt through shearing and stirring, and adding a certain proportion of special stabilizer to form SBS*** mixture, and modifying asphalt by using the good physical properties of "SBS".
Extended data
Use of modified asphalt
Highway use
Many changes have taken place in modern highways and roads: the traffic flow and driving frequency have increased sharply, the axle load of freight cars has increased continuously, and one-way driving with separate lanes has been widely implemented, which requires further improvement of the anti-fluidity of pavement, that is, the ability to resist rutting at high temperature; Improve flexibility and elasticity, that is, crack resistance at low temperature; Improve wear resistance and prolong service life.
Long-span prestressed roof panels are widely used in modern buildings, which require that the roof waterproof material adapt to large displacement, be more resistant to harsh high and low temperature weather conditions, have good durability, be self-adhesive, be convenient for construction and reduce maintenance workload. These changes in the use environment pose a severe challenge to the performance of petroleum asphalt. In order to meet the above demanding requirements, people began to pay attention to the modification of petroleum asphalt.
After decades of research and development, a wide variety of modified road asphalt, waterproofing membrane and coatings have appeared, showing certain practical engineering effects. However, in view of the fact that the price of modified materials is usually 2~7 times higher than that of ordinary petroleum asphalt, users have not fully grasped the engineering properties of materials, and the output of modified asphalt has grown slowly.
At present, modified road asphalt is mainly used in airport runways, waterproof bridge decks, parking lots, sports fields, heavy traffic pavements, intersections, road bends and other special occasions. During this period, Europe applied modified asphalt to the maintenance and reinforcement of road network, which greatly promoted the wide application of modified road asphalt.
water proofing work
Modified asphalt waterproofing membrane and coating are mainly used for waterproofing of high-grade buildings. With the progress of science and technology and the development of economic construction, the variety development and production technology of modified asphalt will be further promoted. The variety and preparation technology of modified asphalt depend on the type and dosage of modifier and the composition and performance of matrix asphalt (original asphalt).
Because there are many kinds and shapes of modifiers, in order to form a uniform material for engineering application with petroleum asphalt, various types of modifiers have been evaluated for many years, and corresponding formulas and preparation methods have been developed, but most of the modified asphalt that has been applied to engineering at present belongs to patented technology and patented products.
classify
Rubber and thermoplastic elastomer modified asphalt
Including: natural asphalt rubber, SBS modified asphalt (the most widely used), styrene-butadiene asphalt rubber, chloroprene asphalt rubber, butadiene asphalt rubber, butyl asphalt rubber, waste rubber and recycled asphalt rubber, and other asphalt rubber (such as ethylene propylene rubber, nitrile rubber, etc.). ).
Plastic and synthetic resin modified asphalt
Include polyethylene modified asphalt, ethylene-vinyl acetate polymer modified asphalt, polystyrene modified asphalt, paulownia resin modified asphalt, epoxy resin modified asphalt and alpha-olefin random polymer modified asphalt.
* * * Mixed polymer modified asphalt
Two or more polymers are added to asphalt at the same time to modify asphalt. The two or more polymers mentioned here may be two separate polymers, or so-called polymer alloys that are pre-mixed to form an interpenetrating polymer network.
Reference source: Baidu Encyclopedia-Modified Asphalt