PE改性沥青及沥青混合料性能研究

Study on Performance of PE Modified Asphalt and Asphalt Mixture

【目的】研究聚乙烯(Polyethylene,PE)改性沥青及沥青混合料性能,分析PE改性沥青混合料工程适用性。【方法】制备PE改性沥青及沥青混合料,通过DSR试验评价老化前后PE改性沥青性能,通过马歇尔试验和车辙试验评价PE改性沥青混合料性能。【结果】结果表明:老化前,在相同测试温度下,随着改性沥青中PE改性剂掺量的增加,改性沥青复合模量和车辙因子先增加后减小,在PE掺量为6%时达到峰值。老化后,改性沥青复合模量呈整体增大趋势,相位角呈减小趋势,车辙因子提高,PE改性剂掺量为6%时,提高幅度最大。随着混合料中PE掺量的增加,改性沥青稳定度、马歇尔模数、动稳定度逐渐增大,流值和车辙深度逐渐减小。PE掺量为6%时,流值为2.36 mm,动稳定度已达到5000次/mm以上。【结论】综合考虑改性混合料性能和工程造价,PE改性剂掺量宜选择6%。PE改性沥青混合料性能满足工程应用的要求。

[Purposes]This paper aims to study the performance of polyethylene(PE)modified asphalt and asphalt mixture,and explore the engineering applicability of PE modified asphalt mixture.[Methods]PE modified asphalt and asphalt mixture were prepared.The performance of PE modified asphalt before and after aging were evaluated by DSR test,and the performance of PE modified asphalt mixture was evaluated by Marshall test and rutting test.[Findings]The results show that before aging and at the same testing temperature,as the amount of PE modifier in the modified asphalt increases,the composite modulus and rutting factor of the modified asphalt first increase and then decrease,reaching a peak at a PE content of 6%.After aging,the composite modulus of modified asphalt shows an overall increasing trend,and the phase angle shows a decreasing trend,and the rutting factor increases.When the content of PE modifier is 6%,the maximum increase is observed.As the PE content in the mixture increases,the stability,Marshall modulus,and dynamic stability of modified asphalt gradually increase,while the flow value and rutting depth gradually decrease.When the PE content is 6%,the flow value is 2.36 mm,and the dynamic stability has reached over 5000 times/mm.[Conclusions]Taking into account the performance and engineering cost of the modified mixture,it is recommended to choose a 6%content of PE modifier.The performance of PE modified asphalt mixture meets the requirements of engineering applications.