疲劳当量温度计算方法研究

Research on Fatigue Equivalent Temperature Calculation Method

现行沥青路面设计规范以15℃作为测定沥青混合料疲劳性能的试验温度,忽略了地区之间存在明显的温度差异。根据路面弹性力学层状理论,对控制应力与应变2种疲劳加载模式进行分析,讨论了适用于路面实际疲劳状况的加载模式。分析了影响沥青路面疲劳寿命的因素,并采用SHELL方法,根据Miner法则计算疲劳当量温度,提出了日疲劳当量温度的计算公式,计算了我国8地区的年疲劳当量温度,讨论了不同地区疲劳当量温度的取值范围和取值方法。研究结果表明,控制应变模式较适用于我国路面实际情况,不同地区路面疲劳试验温度与气温和沥青层厚度之间存在e指数函数关系。

Existing norms regarded 15 ℃ as the test temperature of asphalt mixture fatigue properties which neglected the obviously temperature differences between various areas. By comparing two loading patterns of controlling the stress and strain, the loading pattern suitable to the actual road fatigue conditions was discussed, in which the impact factors of fatigue life of asphalt pavement were analyzed. By adopting SHELL methods based on the Miner＇s rule, the fatigue equivalent temperature was computed, the formula of day fatigue equivalent temperature was educed, with which the annual fatigue equivalent temperature for eight regions was calculated and fatigue equivalent temperature range of the different regions were discussed. The result shows that （1） the strain control mode is fitter for the actual road conditions in China; （2） there exists the relationship of e exponential function among road fatigue test temperature.