钢桥面浇注式沥青+改性沥青SMA铺装结构疲劳抗裂性能评估

摘要:

为评价钢桥面铺装材料抗疲劳开裂性能,采用四点弯曲试验进行不同温度和应变条件下的高弹改性SMA10疲劳试验,建立不同温度下的疲劳行为方程；通过有限元模型提取铺装层顶面最大弯拉应力,计算SMA10在不同温度区间疲劳损伤度,建立钢桥面铺装疲劳开裂预估模型。研究结果表明,温度和应变对钢桥面铺装开裂影响显著；温度每升高10℃,高弹改性SMA10的疲劳寿命提高4~5倍；应变条件和疲劳寿命之间具有很好的指数函数关系,其相关性系数均大于0.9；通过预估模型结果表明,浇注式沥青混合料GA10+高弹改性沥青SMA10结构的疲劳开裂寿命为16年,其预估结果为钢桥面铺装方案的选择提供了理论依据。

Abstract:

In order to evaluate the fatigue cracking resistance of steel bridge deck pavement materials, It is carry out the high elastic modified SMA10 fatigue test under different temperature and strain conditions by four point bending test, and establish the fatigue behavior equation under different temperature; the maximum bending tensile stress of the pavement top surface was extracted through the finite element model, the fatigue damage degree of SMA10 in different temperature range was calculated, and the fatigue cracking prediction model of steel bridge deck pavement was established. The results show that temperature and strain have a significant effect on the cracking of steel bridge deck pavement; the fatigue life of high elastic modified SMA10 increases by 4-5 times when the temperature increases by 10 ℃; there is a good exponential function relationship between strain condition and fatigue life, and the correlation coefficient is greater than 0.9; the prediction model results show that The fatigue cracking life the of GA10 + high elastic modified asphalt SMA10 structure is 16 years, and the predicted results provide a theoretical basis for the selection of steel deck pavement scheme.