基于MSCR试验多聚磷酸改性沥青高温性能评价

High Temperature Performance Evaluation of PPA Modified Asphalt Based on Multiple Stress Creep Recovery Test

【目的】探讨多聚磷酸(PPA)改性沥青的高温性能。【方法】对不同多聚磷酸掺量的改性沥青进行多应力蠕变恢复试验,并通过试验分析基质沥青和RTFOT试验后PPA改性沥青在3.2 kPa剪切应力下平均不可恢复蠕变柔量Jnr3.2值、不可恢复蠕变柔量相对差异Jnrdiff和PG高温连续分级温度HT等技术参数。【结果】试验结果表明,随着PPA掺量的增加,PPA改性沥青结合料的3.2 kPa剪切应力下平均不可恢复蠕变柔量Jnr3.2减小、不可恢复蠕变柔量相对差异Jnrdiff增大、PG高温等级提升。【结论】PPA改性沥青结合料的高温性能得到明显改善,沥青黏弹性能对于应力变化的敏感性增强。

[Purposes]This paper aims to explore the high temperature performance of PPA modified asphalt binder.[Methods]MSCR tests on different content of PPA modified asphalt binder were carried out.Through the tests,technology parameters such as average non-recoverable creep compliance under 3.2 kPa shear stress(Jnr3.2),stress sensitivity index(Jnrdiff)and high continuous grading temperaturewere analyzed.[Findings]The tests results indicated that with the increase of PPA content,average non recoverable creep compliance under 3.2 kPa shear stress(Jnr3.2)decreases,stress sensitivity index(Jnrdiff)increases,and high continuous grading temperatureincreases.[Conclusions]High temperature performance of PPA modified asphalt binder were improved,the viscosity of the asphalt can be enhanced with respect to stress variations.