基于敏感度的沥青路面结构应力传递行为

Stress Transfer Behavior of Asphalt Pavement Structure Based on Sensitivity

针对沥青路面结构层材料设置协调性缺乏评价指标的问题,通过力学计算,提出了采用力学参数敏感度和应力传递路径当量包络面积两个指标,以评价沥青路面结构层材料设置协调性;进一步开发了当量包络面积计算软件,定量评价协调性的同时,将各个结构层材料工作区间及力学传递行为可视化、当量化。结果表明:弯沉敏感度可评价结构整体的刚性,应力敏感度可评价各层材料的应力分布均匀性及利用效率;通过应力传递路径可视化,当量包络面积可定量评价应力传递行为;云罗试验路FWD弯沉测试、反算模量及路面病害调查结果验证了所提指标的合理性。提出的指标及研究思路可弥补现行规范仅通过疲劳寿命来判别路面结构设置合理与否的不足,可为路面结构优化设计提供思路。

In view of the lack of evaluation indexes for the coordination of asphalt pavement structure layer materials,the sensitivity of mechanical parameters and equivalent envelope area of stress transfer path were proposed to analyze the stress transfer behavior of asphalt pavement structure through mechanical calculation.Software was developed to calculate the equivalent envelope area that can quantitatively and equivalently evaluate the coordination among different layers and visualize the mechanical transfer behavior of each structural layer.The results show that the deflection sensitivity can evaluate the rigidity of the whole structure,and the stress sensitivity can evaluate the stress distribution uniformity and utilization efficiency of each layer.Through visualization of stress transfer path,equivalent envelope area can quantitatively evaluate stress transfer behavior.The rationality of the proposed indexes was verified by FWD deflection test,inverse modulus and pavement disease investigation results of Yunluo test road.The proposed indexes and research ideas can make up for the deficiency that the current code only uses fatigue life to judge whether the pavement structure is reasonable or not,and can provide ideas for the optimization design of pavement structure.