钢桥面铺装材料疲劳性能研究

针对钢桥面铺装层容易出现疲劳开裂与车辙破坏的特点,提出采用4种有代表性的铺装层沥青混合料,通过应变控制模式下的四点弯曲疲劳试验方法,研究其疲劳特性以提高钢桥面铺装层的抗疲劳耐久特性和高温稳定性。通过多个应变水平下的疲劳试验,分析了沥青混合料劲度模量与改性沥青品质、疲劳寿命、滞后角的关系,验证了疲劳寿命与累积耗散能在双对数坐标下的线性关系,得出不同改性沥青混合料的疲劳曲线和疲劳方程。不同的铺装层材料很难建立相同的疲劳预测模型,只能根据直接的疲劳试验获得混合料的抗疲劳耐久特性。

Study on Steel Deck Pavement Fatigue Performance

Based on the properties of easily appearing fatigue crack and rut failure of the steel bridge paving,four representative pavement asphalt mixes which have been studied on fatigue characteristic have been put forward to improve the resistances of steel deck pavement against fatigue crack and high-temperature stability through 4-point bending fatigue testing method of strain controlling mode.The relations of asphalt mixes stiffness modulus with modified asphalt quality,stiffness modulus with fatigue life,stiffness modulus with hysteresis angle are analyzed through fatigue experiment of several strains level.We have verified the relation of fatigue life with cumulative hysteresis loop area is linear in double logarithm coordinates,obtaining fatigue curve and fatigue equation of different modified asphalt mixtures.It is difficult to establish the same fatigue forecast model of different steel deck pavement.We can obtain the mixtures performance of durable anti-fatigue only according to the fatigue experiments.