High-dosage activated rubber powder modified asphalt and preparation method thereof

The invention discloses high-dosage activated rubber powder modified asphalt and a preparation method thereof. The modified asphalt is prepared from the following components in parts by weight: 2-6 parts of a performance additive, 35-50 parts of activated rubber powder, 3-7 parts of aromatic oil, 3-7 parts of a coupling agent and 65-80 parts of matrix asphalt. The preparation method of the modified asphalt comprises the following steps: mixing and stirring the activated rubber powder, the aromatic oil and the coupling agent for 10-15 minutes; heating the matrix asphalt to 160-170 DEG C, keeping the temperature constant, adding the obtained mixed slurry into the matrix asphalt, and carrying out primary shearing; and heating to 180-200 DEG C, adding a modification auxiliary agent, and carrying out second-stage shearing, so as to obtain the composite material. According to the invention, silica sol is adopted to modify an auxiliary agent, and supercritical and microwave synergistic treatment is carried out to ac