用测力延度试验评定聚合物改性沥青低温性能

Evaluation of Low Temperature Performances of Polymer Modified Asphalts by Force-Ductility Test

利用自制测力延度仪对SBS,SBR,EVA,PE聚合物改性沥青的低温测力延度特性分别进行了测试研究,分析了聚合物种类及掺量对聚合物改性沥青延度、最大拉力和粘韧性等低温测力延度指标的影响.试验结果表明:随PE,EVA含量的增加,聚合物改性沥青最大拉力变大,而SBS和SBR含量对聚合物改性沥青最大拉力几乎没有影响;SBS,EVA含量的增加会明显提高聚合物改性沥青的粘韧性;聚合物改性沥青粘韧性指标与弯曲流变梁(BBR)试验蠕变劲度指标存在较好的相关性,因此聚合物改性沥青粘韧性指标可用来评价其低温性能.

The low temperature force-ductility performances of SBS, SBR, EVA, PE polymer modified asphalts were studied by force-ductility tests. The effects of polymer type and polymer content on low temperature force-ductility performances including elongation, max force and toughness were investigated. Test results show that max force in force-ductility curves enhances with the increase of the content of PE or EVA while the content of SBS or SBR has light influence on max force. Toughness of polymer modified asphalts improves significantly with the increase of the content of SBS or EVA. Toughness of polymer modified asphalts measured by force-ductility tests has a good correlation with creep stiffness （CS） by bending beam rheometer （BBR） tests, which indicates toughness is of value to evaluate the low temperature performances of polymer modified asphalts.