飞机主起落架构型对道面力学响应的影响

为给飞机和跑道的优化设计提供参考和理论依据，基于弹性层状体系理论，建立了水泥混凝土跑道的三维有限元模型；选取了2组荷载水平相当、主起落架构型差异明显的飞机，对比分析了飞机主起落架构型变化对跑道全宽度位移、应变、板底拉应力以及土基响应深度的影响.模拟结果表明:当荷载相同时，主起落架上机轮总数越多，水泥混凝土道面板位移峰值、板底最大拉应力越小，起落架构型差异导致的道面板位移峰值相差13%左右，板底拉应力相差达35%；起落架间距越小，荷载作用区位移曲线越平缓，荷载作用区拉应变越小，土基响应深度越大，起落架构型变化导致的荷载作用区拉应变相差12%，土基响应深度相差14%；主起落架构型变化对距离荷载作用位置较远区域的竖向位移基本无影响. 

Mechanical Responses of Pavement under Aircrafts with Different Main Landing Gears

In order to provide a theoretical basis for the optimal design of aircraft and pavement, a finite element model of runway was established based on the elastic layered theory to analyze the mechanical responses caused by changing main landing gears. Two sets of aircrafts with the same loads level but different in main landing gear configurations were chosen. The simulation results show that the change of main landing gear configurations influences dramatically on mechanical responses in loading areas. In the condition that aircraft loads are equal, increasing of the total number of wheels on main landing gears will decrease vertical displacement peaks and tensile stresses on panel bottom, the difference of vertical displacement peaks is up to 13% and the difference of tensile stresses on panel bottom is up to 35%. When the spacing between main landing gears is small, displacement curves for the loading areas are gentle and strains in the loading areas are small, but response depth on soil base is large. The difference of strains is up to 12% and the difference of response depth on soil base is up to 14%. The change of the configurations has little effect on vertical displacements far away from loading areas.