SBR改性沥青的低温性能评价

主要对三种国产基质沥青和六种丁苯橡胶(SBR)改性沥青进行了测力延度试验(FDT)、常规技术指标试验以及SHRP的动态剪切仪(DSR)和弯曲梁流变仪(BBR)试验，并且将FDT中采用的粘弹比、拉伸柔度、应变能等指标与沥青的当量脆点(T1．2)、以及损失模量、弯曲劲度模量(S)、斜率(m)相比较，结果显示FDT所选的三个评价指标与SHRP的评价指标有良好的相关性，从而说明了采用FDT对沥青结合料在老化、疲劳综合作用下的低温性能进行评价的经济合理性以及选择三个评价指标的可靠性。

Evaluation of Low Temperature Performance of SBR Modified Bitumen

Low-temperature cracking which is mostly affected by low-temperature anti-cracking performance of bitumen cement is the most important failure of bitumen pavement in permafrost region. Low-temperature performance of three kinds of domestic unmodified bitumen and six kinds of SBR modified bitumen was evaluated by force-ductility test ( hereinafter for short FDT), general experiment,dynamic shear and bending beam rheometer (hereinafter for short DSR,BBR). The result showed the favorable relationship between each evaluating index by contrasting the viscosity-elasticity ratio, tensing-flexibility, yielding strain energy of force-ductility test with equivalent breaking point(T1.2) , loss shear modulus , flexural creep stiffness ,and the velocity of creeping,thus indicating that evaluation of low-temperature performance of modified bitumen by FDT is reasonable.