聚氨酯对环氧树脂改性沥青及混合料性能影响研究

Study on the Infl uence of Polyurethane on the Properties of Epoxy Resin Modifi ed Asphalt and Its mixture

为研究不同用量(20%、30%、40%)聚氨酯(PU)对于环氧树脂(EP)改性沥青及其混合料性能的影响,通过拉伸试验、动态剪切流变和低温弯曲流变试验分析了PU/EP复合改性沥青性能,并利用车辙试验、低温弯曲试验和浸水马歇尔、冻融劈裂试验探讨了复合改性沥青混合料的高温稳定性、低温抗裂性和水稳定性,并以不掺PU的环氧沥青和4%SBS改性沥青混合料为对照组。试验结果表明,加入PU将会降低改性沥青的抗拉强度、车辙因子,但同时提高了沥青的柔韧性和低温性能;加入一定量的PU虽然降低了沥青混合料的高温抗车辙变形能力,但依然远大于4%SBS改性沥青混合料,此外PU加入后明显改善了沥青混合料的低温抗裂性和抗水损害性能。综合各方面性能,建议PU用量为30%~40%。

In order to study the infl uence of dif ferent dosage(20%, 30%, 40%) of polyurethane(PU) on the properties of epoxy resin(EP) modifi ed asphalt and its mixture, the properties of PU/EP composite modifi ed asphalt were analyzed through tensile test,dynamic shear rheological test and low-temperature bending rheological test, and the high-temperature stability, low temperature crack resistance and water stability of composite modifi ed asphalt mixture was discussed by rutting test, low-temperature bending test, immersion Marshall test and freeze-thaw splitting test with epoxy asphalt without PU and 4%SBS modifi ed asphalt mixture as the control group. The test results show that the addition of PU will reduce the tensile strength and rutting factor of the modifi ed asphalt, but improve the flexibility and low temperature performance of the asphalt at the same time;Although the addition of a certain amount of PU reduces the high-temperature rutting resistance of the asphalt mixture, it is still far greater than 4%SBS modified asphalt mixture. In addition, the addition of PU significantly improves the low-temperature crack resistance and water damage resistance of the asphalt mixture. Based on the performance of all aspects, it is recommended that the amount of PU should be 30%~40%.