采用J积分对沥青混合料抗疲劳开裂性能评价研究

Evaluation of Anti-fatigue Cracking Performance of Asphalt Mixture by Using J-integral

疲劳开裂类病害是目前高等级沥青路面出现最多的损坏之一,抗疲劳开裂性能是指材料在重复荷载的作用下抵抗出现裂缝破坏的能力。为了研究断裂韧度JC受材料本身特性的影响,在UTM试验系统上进行了橡胶沥青混合料、SBS改性沥青混合料和掺BF胶粉复合改性沥青混合料的断裂韧度试验,并应用J积分理论来评价沥青混合料的抗疲劳开裂性能。试验结果表明,通过添加SBS、BF对橡胶沥青混合料进行复合改性,材料本身的性能得到改善,其在试验过程中可以吸收更多的能量而不产生结构性破坏,大幅度提高了混合料的抗疲劳开裂性能。

Fatigue crack is one of the most damage to the high grade asphalt pavement at present.The fatigue crack resistance is the ability of the material to resist fracture damage under repeated load. In order to evaluate the effect of material properties on fracture toughness JC,the semi-circular bending test were performed with rubber asphalt mixture, SBS modified asphalt mixture and BF mixed powder modified asphalt mixture in the UTM experiment system.The results showed that by adding SBS and BF, the rubber asphalt mixture was compound modified to improve the performance of the material itself. It can absorb more energy without structural damage during the test, which greatly improved the anti-fatigue cracking of the mixture performance.