Characteristics Evaluation and Application of SBS Composite Modified bitumen Materials in Low Temperature Environment

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Authors

  • Wenxiao Ren Lanzhou University of Technology; Northwest Minzu University, China
  • Ping Li Lanzhou University of Technology, China

Abstract

To improve the resistance of asphalt pavement to low temperature cracking, the study proposes a composite modified asphalt based on styrene butadiene styrene copolymer and rubber crumb. It is also tested for its performance in low temperature environment. The test results indicated that although after aging and freeze-thaw cycles, the creep rate of both modified asphalt and styrene butadiene styrene copolymer/rubber crumb were reduced. However, the creep rate of styrene butadiene styrene copolymer/rubber crumb composite modified asphalt was always better than that of styrene butadiene styrene copolymer modified asphalt. As an example, the creep rate of aged asphalt was 0.37 and 0.44 at -12°C, respectively. When asphalt mixes underwent freeze-thaw cycles and age, their fracture energy densities all drastically decreased. The fracture energy density of styrene butadiene styrene copolymer/rubber crumb composite modified asphalt mixtures, on the other hand, was larger than that of styrene butadiene styrene copolymer modified asphalt mixtures. The above results indicate that the composite modified asphalt with styrene butadiene styrene copolymer/rubber crumb has good rheological ability and freeze-thaw resistance, which can effectively ensure the low temperature performance of asphalt pavement.

Keywords:

SBS, modified bitumen, rheological properties, low temperature properties, cyclic freezing and thawing, crumb rubber