应急机场土质道面疲劳变形特性模型试验

Model Experiment of Fatigue Deformation Characteristic of Emergency Soil Airfield Pavement

为分析应急机场快速修建工程的合理道面结构形式，采用人工加载和道面电液伺服疲劳试验机加载2种方式，对由压实土基、稳定土基层（底基层）和功能性面层组成的典型道面结构疲劳变形特性进行了模型试验．研究了土质道面结构的累积塑性变形、回弹弯沉和弯沉盆曲线随飞机荷载、施加荷载频率和荷载作用次数的变化情况及其平面分布规律．试验结果表明：累积塑性变形随加载频率增大而增大，累积塑性变形与加载次数呈对数关系；弯沉盆曲线形状类似“S”型曲线，可采用四次曲线方程进行拟合；道面结构的早期整体回弹模量增长较快，7～60d龄期内整体回弹模量可达200—500MPa，在数万次通行次数下，土质道面的回弹弯沉小于1mm，表明提出的土质道面结构形式能够满足应急机场强时效性的要求．

To investigate the reasonable pavement structure for rapid construction of emergency airfield, fatigue deformation characteristics of soil airfield pavement were researched respectively by manual loading method and electro-hydraulic servo fatigue testing machine. Through a full-scale model test, the variations of cumulative plastic deformation, rebound deflection and deflection basin curve with load, loading frequency and loading times were discussed. The test results show that cumulative plastic deformation increases with loading frequency, and there exists a logarithmic relationship between it and loading times, the deflection basin curve has approximately an S-style curve and can be fitted well by a quartic polynomial equation. The carrying capacity of pavement structure increases fast at an early stage, holistic elastic modulus runs up to from 200 to 500 MPa in 7 to 60 d, the rebound deflections are less than 1 mm under ten thousands traffic times. The fatigue deformation characteristics of the recommended airfield pavement structure composed of compacted subsoil, cement stabilized soil base （ or subbase） and functional surface course, can meet the requirements of emergency airfield.