摘要
为了研究复合改性剂的掺入对改性沥青混合料使用性能的影响,以70#石油沥青作为基质沥青、蓖麻油植物沥青和岩沥青为改性剂,制备了复合改性剂掺量为0~60%的生物沥青-岩沥青复合改性沥青混合料,设计了级配为AC-20C的沥青混合料,采用车辙试验、Marshall稳定度试验、浸水马歇尔试验、冻融劈裂试验、小梁低温弯曲试验的方法,分析了不同掺量复合改性沥青混合料的Marshall试验稳定度、车辙试验动稳定度、浸水马歇尔试验残留稳定度和冻融劈裂试验残留强度比以及弯曲试验破坏应变。结果表明,复合改性剂掺量不超过最不利掺量时,其掺入将会降低沥青混合料的高温稳定性,随着复合改性剂掺量的继续增加,沥青混合料的高温稳定性逐渐得到提高;掺入复合改性剂后,沥青混合料的水稳定性迅速下降,采用1%消石灰代替部分矿粉后,水稳定性得到明显增强,复合改性剂掺量超过25%时,符合沥青混合料施工技术规范中关于水稳定性的规定;复合改性剂的掺量在最佳掺量范围内,沥青混合料的低温抗裂性得到改善,反之,复合改性剂的掺入对沥青混合料的低温抗裂性产生不利影响,掺量不超过40%时满足冬温区的相应技术要求;路用沥青混合料推荐的复合改性剂掺量范围为25%~40%。
In order to study the performance of modified asphalt mixture with the addition of co-modifier,taking No.70 petroleum asphalt as the matrix asphalt,and castor oil plant asphalt and rock-asphalt as the modifiers,the bio-asphalt and rock-asphalt co-modified asphalt mixture with compound modifier content of 0%-60%is prepared,and the AC-20C graded asphalt mixture is designed.The Marshall test stability,dynamic stability of rutting test,residual stability of immersion Marshall test,residual strength ratio of freezethaw split test and failure strain of flexural test are analysed by using the methods of rutting test,Marshall stability test,immersion Marshall test,freeze-thaw split test,beam low-temperature flexural test.The result shows that(1)When the content of the co-modifier does not exceed the most unfavorable content,its addition will reduce the high temperature stability of the asphalt mixture.As the content of the co-modifier continues to increase,the high temperature stability of the asphalt mixture is gradually improved.(2)After the co-modifier is added,the water stability of the asphalt mixture decreases rapidly.After replacing part of ore powder with 1%slaked lime,the water stability is significantly enhanced.When the content of comodifier exceeds 25%,it complies with the water stability regulation in the asphalt mixture construction technical specification.(3)If the content of the co-modifier is within the optimal content range,the lowtemperature crack resistance of the asphalt mixture will be improved.On the contrary,the addition of the comodifier will adversely affect the low-temperature crack resistance of the asphalt mixture.When it does not exceed 40%,it meets the corresponding technical requirements for the winter temperature zone.(4)For paving asphalt mixture,the recommended content range of co-modifier is 25%-40%.
作者
祝文强
曾梦澜
吴国荣
夏颖林
ZHU Wen-qiang;ZENG Meng-lan;WU Guo-rong;XIA Ying-lin(School of Civil Engineering,Hunan University,Changsha Hunan 410082,China;Jiangxi Transport Design&Research Institute Co.,Ltd.,Nanchang Jiangxi 330022,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2020年第9期1-7,共7页
Journal of Highway and Transportation Research and Development
基金
湖南省交通运输厅科技进步与创新计划项目(201110)。
关键词
道路工程
使用性能
室内试验
蓖麻油植物沥青
岩沥青
复合改性
road engineering
performance
laboratory test
castor oil plant asphalt
rock-asphalt
co-modification
