基于使用性能的浇注式沥青混凝土设计

Mastic asphalt concrete design based on application performance

针对钢桥面铺装浇注式沥青混凝土使用中容易出现的高温车辙、疲劳开裂问题,提出浇注式沥青混凝土"四阶段设计法"确保高温性能与疲劳性能的平衡;基于黏弹力学原理,提出动稳定度为浇注式沥青混凝土高温性能评价指标,通过大型加速加载试验进行验证其可靠性;基于断裂力学和能量法原理,提出冲击韧性为浇注式沥青混凝土疲劳性能评价指标,通过试验建立起冲击韧性和四点弯曲疲劳寿命的关系。研究结果表明:动稳定度可准确反映浇注式沥青混凝土高温抗变形能力;冲击韧性和疲劳性能之间有良好的线性相关性,采用冲击韧性能有效评价浇注式沥青混凝土疲劳性能。

Rutting and fatigue cracking are common ticklish problems in the use of mastic asphalt on the steel bridge deck pavement. ＂Four stage design method＂ was put forward to ensure the balance between the high temperature performance and fatigue performance of mastic asphalt concrete. Based on the theory of viscoelastic mechanics, the dynamic stability was proposed to evaluate the high temperature performance of mastic asphalt, and its reliability was verified by the large accelerated loading test. On the basis of the principle of fracture mechanics and energy method, the impact toughness is presented to evaluate the fatigue performance of mastic asphalt, and the relationship between impact toughness and four-point bending fatigue life was set up by tests. The results show that the high temperature deformation resistance of mastic asphalt concrete can be accurately reflected by the dynamic stability; there is excellent linear relationship between the impact toughness and fatigue performance, and the fatigue performance of mastic asphalt can be effectively evaluated by the impact toughness.