聚酯纤维SMA沥青混合料性能影响因素及制备参数优化研究

Study on Influencing Factors and Preparation Parameter Optimization of Polyester Fiber SMA Asphalt Mixture Performance

摘要:

聚酯纤维拥有良好的物理性能，常被用作沥青玛蹄脂碎石（Stone Mastic Asphalt，SMA）的纤维稳定剂，现行技术规范并未对聚酯纤维技术性能进行明确限制，缺乏可靠施工指导。采用Plackett-Burman因子筛选试验，探究了各个试验因素对聚酯纤维SMA沥青混合料制备过程影响的显著性，并通过正交试验研究了显著因子对SMA混合料路用性能的影响规律，各因素对聚酯纤维SMA沥青混合料试件空隙率影响的显著性顺序为：纤维长度>油石比>压实温度>湿拌时间>纤维含量>拌和温度>干拌时间>预热温度。其中纤维长度、油石比、压实温度对混合料制备的影响具有统计学显著性。通过试验得到的推荐制备参数为：纤维长度6 mm、油石比6.5%、击实温度170 ℃、纤维含量0.5%、预热温度135 ℃、拌和温度180 ℃、干拌时间30 s、湿拌时间90 s。

Abstract:

Polyester fiber has the good physical properties and is often used as a fiber stabilizer of stone mastic asphalt (SMA) mixture. However, the current technical specifications do not clearly limit the technical performance of polyester fiber, and lack of reliable construction guidance. The Plackett-Burman factor screening test is used to explore the significance of each test factor on the preparation of polyester fiber SMA asphalt mixture. The effect of significant factors on the pavement performance of the SMA mixture is studied by an orthogonal test. The significant order of influence of each factor on voidage of polyester fiber SMA asphalt mixture is the fiber length > asphalt-aggregate ratio > compaction temperature > wet mixing time > fiber content > mixing temperature > dry mixing time > preheating temperature. The effects of fiber length, asphalt-aggregate ratio and compaction temperature on the preparation of the mixture are statistically significant. The recommended preparation parameters obtained by the tests are the polyester fiber length 6 mm, asphalt-aggregate ratio 6.5%, compaction temperature 170 °C, fiber content 0.5%, preheating temperature 135 °C, mixing temperature 180 °C, dry mixing time 30 s and wet mixing time 90 s.