测力延度试验以及韧性比评价指标的研究

通过采用测力延度试验(以下简称FDT试验),对多种SBR改性沥青进行低温性能研究,将韧性比RT/V同延度、拉伸柔度、屈服应变能、SBR当量劲度等沥青性能评价指标进行对比分析,同时对其拉伸机理采用断裂力学理论进行了深入的分析。结果表明,韧性比RT/V越大,沥青的低温抗裂性能越好,反之低温性能越差;而且RV/E与BBR试验的m值有良好的相关性。从而验证了测力延度试验方法的可行性,也说明采用韧性比作为低温性能的评价指标是合理的。

Research of Force-ductility Test and Toughness Ratio Index

Low-temperature cracking that is mostly affected by low-temperature anti-cracking performance of bitumen cement is the most important failure of bitumen pavement in permafrost region,so it is important to choose appropriate evaluating measure and index.Force-ductility test(FDT) method and evaluation index of low temperature performance of asphalt binder are studied.All methods and index are based on qualitative analysis,to find out a quantitative index suitable to local condition and an experiment method.Six kinds of SBR modified bitumen was evaluated by the force-ductility test.It shows the feasibility of force-ductility test and rationality of toughness ratio by contrasting with ductility,tensing-flexility,yielding strain energy,SBR equivalent stiffness.At the same time,the the mechanism of bitumen is also discussed by crack mechanics.