The invention discloses an
asphalt modifier, a preparation method thereof, modified
asphalt and a preparation method and application thereof. The
asphalt modifier comprises a base
polymer, a flexibilizer, a compatilizer, a reinforcing agent, an anti-aging agent and a stabilizer, wherein the base
polymer is SBS, and the flexibilizer is a mixture of SEBS and POE. The preparation method comprises the following steps: premixing, carrying out
melt blending, adding the reinforcing agent, the anti-aging agent and the stabilizer in a
molten state, uniformly mixing, extruding, cooling and
pelletizing to obtain the granular modifier. The modified asphalt is prepared by adding the asphalt modifier accounting for 3-8% of the weight of the base asphalt into the matrix asphalt, heating, shearing and mixing. According to the
system, through a synergistic
toughening mechanism of elastic
recovery and
plastic energy consumption and comprehensive design of reinforcement,
aging resistance and cross-linking stability, the modified asphalt has excellent low-temperature
ductility,
fracture toughness and fatigue life, the high-temperature
softening point and storage stability are remarkably improved, and the modified asphalt is suitable for road
pavement engineering in heavy-load and high-temperature severe cold areas.