The invention discloses a composite modified
asphalt material applicable to an anti-crack layer with a pavement structure and a preparation method of the composite modified
asphalt material. The composite modified
asphalt comprises the following components by weight: 83.2-87.6 parts of substrate asphalt, 3.1-4.2 parts of
thermoplastic styrene butadiene rubber (SBS), 1.3-1.7 parts of
powder butadiene styrene rubber (PSBR), 5.3-6.7 parts of desulfuration rubber
powder, 1.8-2.5 parts of acetyl
tributyl citrate (ATBC), and 0.9-1.7 parts of
accelerant, the sum of the parts in weight is 100, the
accelerant is rubber filling oil. The composite modified asphalt is applicable to the anti-crack layer with the pavement structure; the anti-crack layer is usually used for a rigid-flexible composite pavement layer for additionally paving asphalt
surface layer on a concrete rigid base layer with seams (old concrete pavement), also can be used for semi-rigid base
asphalt pavement, so that
delay the forming and expanding of reflection cracks can be delayed, the capability of the pavement structure is improved to
resist fatigue cracks, the
service quality of the pavement structure is improved, and the service life of the pavement structure is prolonged.