胶粉/SBS复合改性沥青及混合料抗裂性能研究

Research on crack resistance of rubber powder/SBS composite modified asphalt and mixture

为研究不同热氧老化程度的胶粉SBS复合改性沥青及混合料的抗裂特性,设计了胶粉掺杂度为6%,9%,12%,15%和18%的复合改性沥青及混合料,分别对沥青和混合料进行了不同程度的室温模拟老化,并对老化后的复合改性沥青进行了频率扫描实验,对老化后混合料进行了半圆弯曲实验。测试结果显示随着热氧老化程度的增加,复合改性沥青的G-R常数增加,复合改性沥青混合料的FI值降低,抗裂性能衰减。当胶粉掺量不大于12%时,复合改性沥青及混合料的抗裂性能好于SBS改性沥青,但当胶粉掺量增加至15%和18%时,复合改性沥青和混合料的抗裂性能不如SBS改性沥青。胶粉掺量为12%时,复合改性沥青的抗裂性能最佳。

In order to study the anti-cracking properties of rubber powder SBS composite modified asphalt and mixtures with different degrees of thermal-oxidative aging,composites with rubber powder doping levels of 6%,9%,12%,15% and 18% were designed.Modified asphalt and mixture,and simulated aging of asphalt and mixture at different degrees at room temperature respectively,high frequency sweep experiment on composite modified asphalt,and semicircular bending experiment on composite modified asphalt mixture.The test results show that with the increase of the degree of thermal oxidation aging,the G-R constant of the composite modified asphalt increases,the FI value of the composite modified asphalt mixture decreases,and the crack resistance decreases.When the content of rubber powder is less than or equal to 12%,the crack resistance of the composite modified asphalt and mixture is worse than that of SBS modified asphalt,but when the content of rubber powder increases to 15% and 18%,the composite modified asphalt and mixture the crack resistance is not as good as that of SBS modified asphalt.When the content of rubber powder is 12%,the crack resistance of composite modified asphalt is the best.