应用测力延度试验评价改性沥青的低温性能

Research on Mechanism and Evaluating Index of Force-Ductility Test

低温开裂是低温地区沥青路面发生的主要病害,而沥青结合料的低温抗裂性能是病害的主导因素,因此选择合适的评价方法和合理的评价指标显得尤为重要。本文主要对6种SBR改性沥青进行测力延度试验、常规技术指标试验以及SHRP的弯曲梁流变仪试验,通过将FDT与常规技术指标试验、SHRP的弯曲梁流变仪试验进行相关性分析,验证了应用FDT评价改性沥青的低温性能经济合理性以及采用粘弹比RV E、拉伸柔度f、屈服应变能E作为评价指标的正确性,同时也对其拉伸机理进行了研究分析。

Low-temperature cracking that is mostly affected by low-temperature anti-cracking performance of bitumen concret is the most important distress of bitumen pavement in low temperature region,so it is important to choose appropriate evaluating method and index.Six kinds of SBR modified bitumen was evaluated by force-ductility test,general experiment,and SHRP bending beam rheometer in this paper.Showing the favorable relativity of each evaluating index by contrasting with the viscosity-elasticity ratio,tensing-flexility,yielding strain energy of force-ductility test.It can be seen that evaluation of low-temperature performance of modified bitumen by FDT is reasonable.This paper also discusses the mechanism of FDT.