温拌LDPE改性沥青混合料性能研究

选择Sasobit和Evotherm 3G两种温拌剂对温拌LDPE沥青混合料制备工艺和性能进行研究。首先,比较变温等体积法和等黏温度法两种方法,并确定两种温拌混合料的拌和及击实温度。在此基础上,分别采用车辙试验、低温弯曲试验、中点加载弯曲试验以及冻融劈裂试验评价70#、LDPE、Sasobit-LDPE以及3G-LDPE四种沥青混合料的高温性能、低温性能、疲劳性能和水稳定性。结果表明,两种温拌技术均是可行的,Sasobit和3G温拌技术可使施工温度降低20℃和15℃。与热拌LDPE沥青混合料相比,Sasobit温拌沥青混合料具有更好的高温性能和水稳定性,在高应力比条件下抗疲劳性能更好,低温性能虽变差,但是优于70#沥青混合料;3G温拌沥青混合料的高温性能,低温性能以及水稳定性则与热拌LDPE沥青混合料各项性能较为接近,抗疲劳性能变差,但是优于70#沥青混合料。

Study on the Performance of Warm Mix LDPE Modified Asphalt Mixture

Sasobit and Evotherm 3G,two kinds of warming agents,are selected to study the preparation process and performance of warm mix asphalt(WMA)mixture.First,the mixing and compaction temperatures of the two warm mix mixture are determined by the variable temperature equal volume method and the equal viscosity temperature method.On this basis,the rutting test,low temperature bending test,midpoint loading bending test and freeze-thaw split test are used to evaluate the high temperature performance,low temperature performance,fatigue performance and water stability of 70#,LDPE,Sasobit-LDPE and 3G-LDPE asphalt mixtures.The results show that both warm mixing techniques are feasible.Sasobit and 3G warm mixing technology can reduce the construction temperature by 20℃and 15℃.Compared with LDPE asphalt mixture,Sasobit asphalt mixture has better high temperature performance and water stability,better fatigue resistance under high stress ratio conditions,although the low temperature performance is worse,but better than 70#Asphalt mixture.The high temperature performance,low temperature performance and water stability of 3G WMA mixtureare close to the performance of hot mix LDPE mixture,the fatigue resistance is worse,but better than 70# asphalt mixture.