脱空对刚性道面板应力分布的影响及临界脱空状态

Effect of Support-loss on Stress Distribution of Airport Concrete Pavement Slab and Critical Support Condition

摘要:

基于层间弹簧模型提出支承状态模拟方法，构建刚性道面板数值仿真模型。考虑不同飞机荷载和接缝状态，分析脱空影响下的道面板荷载应力增幅、位置偏移及重分布规律。结果表明：层间弹簧模型可准确地模拟脱空导致的刚性道面板支承损失以及不同脱空状态；随着脱空加剧，脱空区边缘的荷载应力增大，最大荷载应力在板厚方向上的位置由板底转移至板顶；当脱空区内最大荷载应力超过健康状态（即无脱空）下临界荷位的峰值应力时，该脱空状态即为临界脱空状态。相比传统弯沉指标，临界脱空状态能够更准确地反映脱空对道面结构的影响。

Abstract:

By using an array of spring elements to simulate the support condition under airport concrete pavement slab， a numerical simulation model was developed to study the variation of aircraft-induced strain under poor support conditions. The different aircraft loads and load transfer states at joints were considered. A full-scale experiment was conducted for model verification. As indicated in the results， the spring-based method that simulates the support condition performs well on solving the mechanical responses. Support-loss would increase the tensile strains at the edge of support-loss region， and the location where critical tensile strain occurs would be transferred from the bottom to the top of the pavement. When the critical tensile strain under poor support condition exceeds the maximum tensile strain under intact condition， the support condition was determined as the critical support condition. Compared with the conventional evaluation methods of support condition （e.g. deflection-based methods）， the critical support condition can reflect the effect of support-loss more accurately.