布敦岩沥青改性沥青混合料低温抗裂性能试验研究

Experimental Research on Low Temperature Anti-cracking Performance of BRA Modified Asphalt Mixtures

通过弯曲试验和冻断试验研究了经受紫外老化前后的布敦岩沥青(BRA)改性沥青混合料的低温抗裂性能,结果表明:紫外老化前BRA改性沥青混合料破坏应变比基质沥青混合料提高248μξ,冻断温度降低0.2℃,变化均不大;紫外老化后BRA改性沥青混合料比基质沥青混合料提高1 310μξ,提高幅度超过1倍。这表明,BRA改性沥青混合料在多因素耦合作用下的低温抗裂性能比基质沥青混合料更优,其路用性能衰变速率更慢。同时,结合试验结果提出了沥青混合料的开裂曲线,并尝试建立了沥青混合料的开裂计算模型。

Bending test and freeze-off test were studied before and after aging the Buton rock asphalt （BRA） modified asphalt mixture with stand UV aging crack resistance at low temperature. The results show that UV aging former BRA modified asphalt mixture failure strain than asphalt mixes to improve 248μξ, freeze-off temperature decreases 0. 2℃. After UV aging BRA modified asphalt mixture than asphalt mix to improve 1 310μξ, increase rate more than doubled. This suggests that BRA modified asphalt mixture at low temperature cracking resistance is better than the multivariate coupling matrix asphalt, the road performance slower decay rate. Meanwhile, combined with the test results, this paper presented cracking curve, and tried to establish a computational model of cracking of asphalt mixture.