道基不均匀分布下通用机型轮载对机场道面力学性能影响研究

Influence of General Aircraft Wheel Load on Mechanical Properties of Airfield Pavement under Uneven Distribution of Road Foundation

为研究道基水平方向不均匀分布对机场道面板力学性能的影响,建立飞机荷载-道面结构-不均匀道基三维模型,采用数值模拟方法分析多板协同受力模式下基顶反应模量变化对道面板弯拉应力影响,探讨通用机型(空客A320和波音B737-800)轮载作用时基顶反应模量变化和道面板厚度对道面板力学性能以及接缝传荷系数的影响,同时基于缩尺试验对数值模拟结果进行验证。研究结果表明:对于A320机型,当道基水平不均匀分布时混凝土板弯拉应力增大,基顶反应模量变化率由0%增加至65.46%时,轮载作用于传力杆接缝板边时道面板弯拉应力由4.06 MPa增加至5.73 MPa,超过极限弯拉应力;增加板厚能够有效地提升刚性道面板受力安全时基顶反应模量变化率的取值范围;道面板接缝传荷系数随着基顶反应模量变化率的增加而增大,基顶反应模量变化率从6.84%增加至56.30%时,道面板传荷系数增加2.44%;室内缩尺试验验证了道基不均匀分布对传荷系数的影响规律。在道面板设计时,应充分考虑道基水平方向不均匀分布对道面板力学性能的影响,避免在服役期间过早出现结构破坏。

To study the influence of uneven distribution of road foundation in the horizontal direction on the mechanical properties of airport pavement panels,a three-dimensional model of aircraft load-pavement structure-uneven road foundation was established.Numerical simulation methods were used to analyze the influence of changes in the reaction modulus of the foundation top on the flexural tensile stress of the pavement panel under multi-plate collaborative force mode.The influence of changes in the reaction modulus of the foundation top and pavement panel thickness on the mechanical properties of pavement panels and load transfer coefficients of joints under wheel load for general aircraft models(Airbus A320 and Boeing B737-800)was discussed.Meanwhile,the numerical simulation results based on scaled experiments were verified.The research results indicate that:for the A320 aircraft,when the horizontal distribution of the road foundation is uneven,the flexural tensile stress of the concrete slab increases,and the rate of change in the reaction modulus of the foundation top increases from 0%to 65.46%.When the wheel load acts on the edge of the joint plate of the transmission rod,the flexural tensile stress of the pavement slab increases from 4.06 MPa to 5.73 MPa,exceeding the limit value of the ultimate flexural tensile stress.Increasing the slab thickness can effectively improve the range of values for the change rate of the reaction modulus of the foundation top when the rigid pavement panel is under safe stress.The load transfer coefficient of the pavement panel joint increases with the increase of the change rate of the reaction modulus of the foundation top.When the change rate of the reaction modulus of the foundation top increases from 6.84%to 56.30%,the load transfer coefficient of the pavement panel increases by 2.44%.The indoor scaled experiment verifies the influence rule of uneven distribution of road foundation on the load transfer coefficient.It is concluded that the influence of uneven distribution of road foundation in the horizontal direction on the mechanical properties of pavement panels should be fully considered in the design of pavement panels to avoid premature structural damage during service.