Modern transportation is developing in the direction of high traffic density, axle load, and canalized traffic, which puts forward higher requirements on the road performance of the asphalt surface layer. In order to improve the performance of the surface layer, people have explored a variety of measures, of which the fiber additives in the asphalt mixture is a successful method at home and abroad, such as SMA, OGFC, bridge deck pavement and ordinary asphalt concrete Both are used.
When short fibers are added to asphalt concrete, there is a complex interaction between fiber and fiber, and fiber and surrounding matrix due to fiber discontinuity, it will significantly affect the toughness and failure process of composite materials, with elasticity, The role of thickening, strengthening and toughening. The fibers used in asphalt concrete at home and abroad are mainly lignin fiber, chemical short fiber and inorganic short fiber, etc., and their performance effects are different. Among them, due to the shortcomings of lignin fiber can not be regenerated and the high price of polymer fiber, basalt short fiber is used for asphalt concrete in large quantities abroad. The test data of basalt short fiber and other fibers are shown in Table 4. The data shows that short basalt fibers are equivalent to other fibers in terms of resistance to water damage and improved oil-rock ratio; they have advantages in high temperature rutting resistance, low temperature bending resistance, leakage analysis and anti-scattering performance. In addition, basalt short fiber has the advantages of low price, flame retardant and smoke suppression, and is especially suitable for flame retardant asphalt surface layer in tunnels.
Basalt ore is a common material for asphalt mixed aggregates. The basalt gravel asphalt pavement composed of basalt gravel as the main aggregate has high temperature resistance to deformation and frost resistance, good resistance to water damage, and wear resistance and pressure resistance. It can be used for highways and highways, raw materials Wide variety of sources. At present, the Ministry of Communications issued the standard "JTG F40-2004 Highway Asphalt Pavement Construction Technical Specification" No. 4.11 "Fiber Stabilizer", it has been clearly proposed that "fiber stabilizers mixed in asphalt mixture should use lignin fiber, "Mineral fibers, etc.", "Mineral fibers should be made of ores such as basalt". At the same time, due to the defects that lignin fiber cannot be regenerated, the price of polymer fiber is high, and the effect of basalt mineral fiber admixture is good but not environmentally friendly, through the development of technological processes, we have developed short-cut basalt fiber for asphalt concrete. The characteristics of basalt chopped fiber are:
◆Strong affinity with asphalt
◆Good oil absorption effect
◆Excellent high temperature resistance
◆Good mechanical properties
◆Good dispersion
◆Strong resistance to acid and alkali
◆Good anti-aging performance
◆Waterproof erosion and no water absorption