超薄磨耗层高黏弹沥青混合料抗反射裂缝性能

Anti-reflective crack performance of high viscosity and high elasticity asphalt mixture for ultra-thin wear layer

为评价超薄磨耗层用高黏高弹沥青混合料抗反射裂缝性能,采用改进的沥青罩面层测试(overlay tester,OT)试验,研究不同级配、沥青含量和粉胶比对高黏高弹沥青混合料抗裂性能的影响.结果表明,骨架密实型高黏高弹沥青混合料抗反射裂缝性能远高于AC-10和SMA-10,高黏高弹沥青混合料抗裂性能优异主要体现在产生裂缝的初始拉应力较大,抗裂衰减性能良好;增加沥青用量可以提高高黏高弹沥青混合料抗裂衰减性能,增加粉胶比有助于提高高黏高弹沥青混合料初始抗裂强度,但会降低混合料抗裂衰减性能,在粉胶比为0.80~1.20时,强度与抗裂衰减性之间达到较好平衡;为提高超薄磨耗层抗裂性能,建议高黏高弹沥青混合料采用骨架密实结构,最佳油石比范围为7.3%~7.9%,最佳粉胶比范围为0.80~1.20.研究结果可为超薄磨耗层抗反射裂缝性能的提高提供参考.

In order to evaluate the anti-reflective cracking performance of high viscosity and high elasticity asphalt mixture(HVHEAM)for ultra-thin wear layer,the improved overlay tester was used to study the effects of different gradation,asphalt content and filler-asphalt ratio on the anti-cracking performance of the HVHEAM.The results show that the anti-reflection crack performance of the dense skeleton type HVHEAM is much higher than those of AC-10 and SMA-10,and the excellent crack resistance of the HVHEAM is mainly reflected in the large initial tensile stress of cracks simultaneously,it has good crack resistance and attenuation performance.Increasing the asphalt contents can improve the anti-crack attenuation performance of the HVHEAM.Increasing the filler-asphalt ratio helps to increase the initial crack resistance of the HVHEAM,but it will reduce the crack-resistance attenuation performance of the mixture,and a good balance between strength and crack-resistance attenuation is achieved when the filler-asphalt ratio is in the range of 0.8 to 1.2.In order to improve the anti-crack performance of the ultra-thin wear layer,we recommend that the HVHEAM adopt a dense skeleton structure,the optimal asphalt-to-aggregate ratio range is 7.3%to 7.9%,and the optimal filler-asphalt ratio range is 0.8 to 1.2.The research results can provide a reference for improving the anti-reflection crack performance of ultra-thin wear layer.