SBS-SBR 复合改性沥青黏弹特性研究

Study on Sticky Elastic Properties of SBS-SBR Composite Modified Asphalt

摘要:

采用物理共混方法制备SBS改性沥青、SBR改性沥青和SBS-SBR复合改性沥青，基于动态剪切流变仪(DSR)测试沥青在温度扫描模式下的复数模量和相位角，评价沥青的高温性能；采用多应力蠕变恢复试验(MSCR)测试沥青在蠕变加载过程中的应力响应特征，最后基于BBR试验评价沥青的低温性能。结果表明:在沥青中掺入SBS和SBR能够大幅提高沥青的高温抗变形能力，疲劳极限温度能够表征沥青的抗疲劳性能，沥青的粘性特征和疲劳性能具有相关性，基质沥青在高温下具有良好的疲劳特性；MSCR试验结果表明，改性沥青具有显著的弹性恢复特性，沥青的可恢复变形随着应力的增大逐渐降低；低温梁流变试验(BBR)结果显示，掺入SBS与SBR能够提高沥青在低温下的应力松弛能力和抗裂性能。

Abstract:

The physical blending method is used to prepare the SBS modified asphalt, SBR modified asphalt and SBS-SBR composite modified asphalt. Based on dynamic shear rheometer (DSR), the complex number modulus and phase angle of asphalt under the temperature scanning mode are measured, and the high-temperature performance of asphalt is evaluated. The stress response characteristics of the asphalt in the creep loading procedure are measured by the multiple stress creep recovery test (MSCR). Finally based on BBR test, the low-temperature properties of asphalt are evaluated. The results show that the asphalt mixed with SBS and SBR can greatly improve the high-temperature anti-deformation capacity of asphalt. The fatigue limit temperature can represent the anti-fatigue performance of asphalt. The cohesive characteristics and fatigue properties of asphalt are correlated. The matrix asphalt has good fatigue properties at the high temperature. The results of MSCR test show that the modified asphalt has the remarkable elastic recovery character. The recoverable deformation of asphalt gradually decreases with the increase of stress. The result of low-temperature bending beam rheological test (BBR) shows that the mixing of SBS and SBR can improve the stress relaxation capacity and anti-cracking ability of asphalt at the low temperature.