聚芳酯纤维水稳碎石-沥青混合料层间黏结性能

Interlayer Bonding Properties between Polyarylate Fiber-reinforced Cement-stabilized Macadam and Asphalt Mixture

摘要:

为研究聚芳酯纤维水泥稳定碎石与沥青混合料的层间黏结效果，基于复合试件的性能测试研究了层间黏结性能的影响因素。制备了不同组合形式的“水泥稳定碎石+黏层沥青+沥青混合料”复合试件，通过剪切试验、拉拔试验及弯曲疲劳试验分别测试了层间剪切强度、拉拔强度和疲劳寿命。结果表明：复合试件的层间黏结强度峰值存在对应的沥青洒布量范围，约为1.5~1.8 kg/m²，疲劳寿命则随黏层洒布量的增加而增大；SBS改性沥青作为黏层材料时层间黏结强度优于70#沥青；水泥稳定碎石中掺加纤维可进一步提升黏结强度和疲劳寿命，剪切强度和拉拔强度的提升幅度分别为4.5%~12%和3.9%~7.6%，疲劳寿命可提升约10%~44%。黏层沥青类型、洒布量及水泥稳定碎石中的聚芳酯纤维掺量对水泥稳定碎石与沥青混合料的层间黏结效果均有影响。

Abstract:

To study the interlayer bonding effect between polyarylate fiber-reinforced cement-stabilized macadam and asphalt mixture, the influencing factors of interlayer bonding performance are studied according to the performance tests of composite specimens. The composite specimens of "cement-stabilized macadam + tack coat asphalt + asphalt mixture" with different combination forms are prepared. The interlayer shear strength, pull-off strength and fatigue life are measured through shear tests, pull-off tests and flexural fatigue tests, respectively. Results show that the peak value of the interlayer bonding strength of the composite specimens has a corresponding range of asphalt spreading amount, approximately 1.5~1.8 kg/m², and the fatigue life increases with the increase of the spreading amount of the bonding layer. When SBS modified asphalt is used as a bonding material, its interlayer bonding strength is superior to that of 70# asphalt. Adding fibers to cement-stabilized macadam can further enhance the bonding strength and fatigue life, the increase in shear strength and tensile strength is 4.5% to 12% and 3.9% to 7.6% respectively, and the fatigue life can be increased by approximately 10% to 44%. The type of tack coat asphalt, its spreading amount and the dosage of polyarylate fibers in cement-stabilized macadam all have an impact on the interlayer bonding effect between cement-stabilized crushed stone and asphalt mixture.