钢桥面铺装浇注式沥青混合料性能研究

Research on the steel deck pavement performance of pouring asphalt concrete

为研究钢桥面铺装浇注式沥青混合料的性能,对胶结料天然沥青的高温和老化微观机理进行研究,根据马歇尔、硬度、刘埃尔流动度试验确定GMA10浇注式沥青混合料的级配,通过汉堡车辙、弯曲小梁、浸水马歇尔、冻融劈裂、飞散试验以及冲击韧性试验分别对GMA10浇注式沥青混合料的高温、低温、抗水损害及疲劳性能进行评价。研究结果表明:天然沥青可提高改性沥青的高温和老化性能,GMA10浇注式沥青混合料的最佳油石比为11.1%;GMA10浇注式沥青混合料的高温抗车辙性能较差,但组合结构(3.8 cm SMA13+3 cm GMA10)具有较好的高温抗车辙性能;GMA10浇注式沥青混合料的抗水损害性能和低温抗裂性能优于普通热拌沥青混合料,疲劳性能随拌和时间的延长而降低,随拌和温度的提高先提升后减弱;GMA10浇注式沥青最佳拌和温度为210~230℃,最佳拌和温度为120~180 min。

In order to research on the steal deck pavement performance of pouring asphalt concrete,the microscopic mechanism of high temperature and aging of natural asphalt was studied,the gradation of pouring asphalt mixture GMA10 was made sure according to Marshall test,hardness test and fluidity experiment.The high temperature,low temperature,water damage resistant performance,fatigue performance of the GMA10 pouring asphalt mixture were evaluated and analyzed respectively through the Hamburg rutting test,bending beam test,immersion Marshall test freeze-thaw splitting test,Cantabro test and impact toughness test.The results show that natural asphalt binder could improve the high temperature and aging properties of modified asphalt and it better fits GMA10 pouring asphalt mixture.The optimum asphalt ratio of GMA10 was 11.1%.The high temperature performance of only the GMA10 layer was poor,but the upper SMA13 asphalt mixture was good,which conversely made the combination(3.8 cm SMA13+3 cm GMA10)was good anti-rutting performance.The water damage resistance and crack resistance at low temperature of GMA10 asphalt mixture were better than that of hot mix asphalt mixture.The fatigue performance decreased with prolonging mixing time,but it first increased and then decreased with the increase of mixing temperature.The best mixing temperature is 210~230℃,and the best mixing temperature is 120~180 min.