多轮荷载作用下的高模量沥青道面力学响应特性

飞机起落架多轮荷载作用下，道面内部应力应变等力学响应将产生叠加与干涉。本文针对高模量沥青机场道面，通过ABAQUS有限元软件开展道面结构力学响应计算，分析飞机多轮荷载对道面力学响应敏感性，研究高模量沥青混合料在机场道面中的应用效果。结果表明：在飞机主起落架的六轮荷载作用下，道面结构层中产生的应力与路表弯沉的峰值最大，且道面的疲劳寿命最小，在进行道面结构计算与材料组成设计时，应以六轮荷载作为最不利荷载工况；机轮荷载分布的对称性越强，结构内应力与路表弯沉的峰值点位置越靠近荷载包围区域中心；沥青道面变形有一定的时间滞后，卸载后路表弯沉不能立即恢复并存在残余变形，且主起落架轮数越多，滞后时间越长，保留的残余变形越大；中面层采用的高模量沥青混合料可降低道面各层拉应力、压应力、剪应力的应力水平，进而有效地减少机场沥青道面轮辙与疲劳开裂。

Mechanical Response Characteristics of High Modulus Asphalt Pavement Under Multi-wheel Load

Under the loading of multiple wheels of aircraft landing gear, the mechanical response such as stress and strain inside the plane surface will produce superposition and interference. In this paper, aiming at the high modulus asphalt airport pavement, ABAQUS finite element software is used to calculate the mechanical response of the pavement structure, analyze the sensitivity of aircraft multi-wheel load to the mechanical response of the pavement, and study the application effect of high modulus asphalt mixture in the airport pavement. The results show that under the six-wheel load of the main landing gear of the aircraft, the peak values of stress and surface deflection in the pavement structure layer are the largest, and the fatigue life of the pavement is the smallest. In the calculation of pavement structure and material composition design, six-wheel load should be the most unfavorable load condition ; the stronger the symmetry of the wheel load is, the closer the peak point of the internal stress of the structure and the deflection of the road surface is to the center of the load surrounding area. The deformation of asphalt pavement has a certain time lag. After unloading, the deflection of the road surface cannot be recovered immediately and there is residual deformation. The more the number of main landing gear wheels, the longer the time lag, and the greater the residual deformation retained. The high modulus asphalt mixture used in the middle layer can reduce the stress level of tensile stress, compressive stress and shear stress in each layer of the pavement, thus effectively reducing the airport asphalt pavement rut and fatigue cracking.