基于材料非线性的沥青路面结构当量力学分析方法

针对目前沥青路面结构分析中存在的线弹性层状体系假设无法描述材料非线性特性以及结构层模量取值不合理等问题，为了寻找更加符合路面结构非线性服役行为的沥青路面结构分析方法，将材料非线性与层状体系相结合，研究3种典型路面材料模量依赖模型，建立材料模量与结构模量跨越的联系机制，提出了一种基于材料非线性的沥青路面结构分析当量计算方法，并通过足尺环道实测应变结果对方法的可靠性进行了验证。研究结果表明：基于材料非线性的沥青路面结构分析当量计算方法，其计算结果与足尺环道实测结果之间具有良好的相关性，方法可靠、合理，可以作为沥青路面非线性分析的一种计算手段；基于材料非线性原理构建的沥青混合料、半刚性材料和路基土的模量依赖模型，可以用于表征路面结构计算中的材料非线性特性；采用Mises等效应力可作为室内单一应力状态和现场复杂应力状态的联系机制，以协调室内试验模式和现场实际受力状态；当路面结构形式、荷载与环境条件确定时，路面结构的力学响应具有唯一性。所提出的当量计算方法一方面获得了一种确定路面材料回弹模量取值的有效技术途径，另一方面改进了沥青路面结构力学分析的合理性和可靠性，在非线性沥青路面分析理论和计算方法等方面具有一定的学术意义和应用价值。

Equivalent Mechanical Method for Asphalt Pavement Structure Based on Material Nonlinearity

Describing the nonlinear characteristics of a material using the linear elastic layered system is generally considered challenging, whereas the values of the pavement layer moduli obtained in the analysis of asphalt pavement structures are not reasonable. To find a more suitable method to reflect the nonlinear service behaviors of asphalt pavement structures, the material nonlinearities were combined with the layer system, and three typical modulus-dependent models of the pavement material were studied to establish the relationship between material and structural moduli. An equivalent calculation method of the asphalt pavement structure analysis based on material nonlinearity was proposed, and the reliability of the method was verified from the measured strain results of full-scale test track. The calculated results of this method are in good agreement with the measured results of the full-scale test track. The method is observed to be reliable and reasonable, and can be used for nonlinear analysis of asphalt pavements. The modulus-dependent models of the asphalt mixture, semi-rigid material, and subgrade soil, which were built on the principle of material nonlinearity can now be used to characterize the material nonlinear characteristics in the calculation of the pavement structure. The von Mises equivalent stress can be used for the relationship between the single and complex stress states in the field, which can also coordinate the indoor test model and actual stress state. The mechanical response of the pavement structure is unique when its form, load, and environmental conditions are determined. On the one hand, the equivalent calculation method is effective at determining the resilience modulus of the pavement material. On the other hand, it improves the rationality and reliability of the mechanical analysis of the asphalt pavement structure. This study and methods have academic significance and application value to nonlinear asphalt pavement analysis theory and calculation.