昼夜温度及交通量变化对沥青路面响应及性能的影响

Effect of N/D variation in temperature and traffic volume on response and performance of asphalt pavement

现场沥青路面结构承受的交通量及温度都有随昼夜变化的特性,如果交通量较为集中的时段往往也是地表温度较高的时段,则会对路面结构造成较大的破坏。文章利用试验得到的沥青混合料的动态模量主曲线和时间温度转换因子,结合实测的路面结构温度场对这一问题进行了定量分析。分别分析了沥青混合料的动态模量、路面结构的关键力学响应以及荷载对路面结构的破坏率的昼夜变化特性,并比较了冬天和夏天变化特性的不同;结合不同时间的荷载作用破坏率及实测的交通量小时分布系数进行分析,表明按交通量实际分布情况得到的路面结构使用寿命可以比按传统假设的均匀分布情况小10%以上。在路面结构分析和设计中有必要考虑温度及交通量的昼夜变化特性。

Traffic volume and temperature to the spot structures of asphalt pavement are variable with day and night. More damage of pavement structure arises over a period of the higher ground temperature and traffic volume. The main curve of dynamic modulus of asphalt mixture and factors of time - temperature changes, in combination with the measured temperature field of pavement structure, this paper conducted a quantitative analysis on variation of characteristics day and night, including the dynamic modulus of mixture, the critical response of pavement structure, as well as damage rate due to load action, with comparison with the differences in characteristics in both summer and winter. According to analysis on the damage rate at different time and the coefficient of hour distribution of measured traffic volume, the pavement service life obtained from the actual distribution of traffic volume is reduced by more than 10 percent than that from well - distributed situation in the traditional assumption. Therefore, it is necessary to consider the effect of variation in temperature and traffic volume day and night on response and performance of asphalt pavement in the process of design and analysis.