Determining critical loads and maximum mechanical response of representative models is the basis of rigid runway design. With full consideration of load transfer effect of joint and contact between slab and base,3D finite element model of rigid airport runway is established. By using high precision element,the typi-cal loading condition of Boeing747 is simulated and comparative analysis is done with the calculation results. The result shows that horizontal tensile stress is produced by two main landing gears is greater than that is pro-duced by single main landing gears. Therefore the impact of adjacent landing gear should be taken into account for design purpose. When two landing gears are located at the same slab,concrete slab between the gears will produce reverse bend. However,the transverse tensile stress is small that top-down longitude crack will not be induced in Boeing747 loading. Due to superposition of deflection basin,peak vertical displacement in the case of two landing gears loading at the same plate is greater than corner loading of single landing gear. Maximum stress of base in any direction occurs in corner loading condition,therefore it is necessary to take measures to reinforce the base of beneath slab corner.%确定代表性机型的临界荷位与最大力学响应是进行刚性机场跑道设计的基础.采用高精度单元建立刚性机场跑道三维有限元模型,充分考虑接缝传荷作用和面板与基层接触,对Boeing747典型加载工况进行数值模拟,并结合计算结果进行对比分析.研究表明:Boeing7472个主起落架同时加载产生的水平拉应力大于单个起落架加载时的,故跑道设计时应考虑相邻起落架的影响;当2个起落架在同一块板加载时,起落架之间的混凝土板会产生横向反弯,但反弯处横向拉应力较小,故Boeing747加载时不会产生由顶部向下部扩展的纵向裂缝;由于弯沉盆叠加,2个起落架在同一块板加载产生的竖向位移峰值大于单个起落架板角加载时的;基层中各个方向应力在板角加载时最大,因此,有必要对板角处的基层采取一定强化措施.
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