飞机荷载重复作用次数的简化计算方法

对力学-经验型沥青道面结构设计方法中的飞机交通荷载分析方法进行研究,探讨了一种简化的荷载重复作用次数计算方法.通过理论分析,提出了以应力(应变)扩散斜率和等效宽度为中心的荷载重复作用次数简化计算概念.双层体系的结构响应分析表明,等效宽度是结构厚度和上下层结构相对刚度的函数.经过回归分析,给出了等效宽度和结构厚度的线性关系式,回归计算结果与基于道面空间响应得到的等效宽度之间的误差在5%以内.对于多层的道面结构,建议按照力学等效的方法转换成双层结构后进行计算.在此基础上,提出了单轮的荷载重复作用次数计算方法,并详细分析了横向多轮和纵向多轴的影响.基于单机型的计算分析,进一步扩展提出了混合交通条件下的荷载重复作用次数简化计算方法.

Simplified Methods for Calculating Aircraft Load Repetition

Simplified methods for calculating aircraft load repetition are discussed in this paper, which is used in Mechanistic-Empirical pavement design procedure. A simplified concept, which is based on stress/stain spread angle and equivalent width, is put forwarded as the base of load repletion calculating. The results based on double pavement layers analyzing show that the equivalent width is the function of top layer thickness and relative stiffness of the layers. Then, the simplified equations for calculating equivalent width are put forwarded. The width differences between simplified method and spatial response based method are within 5%. For the pavement more than two layers, it can be transfer to two layers according the equivalent approach. Using the equivalent width, load repetition methods are developed for single tire, as well as multiple tires and multiple axles. Furthermore, the equations for considering mixed traffic are put forwarded.