步行和跳跃激励是人行桥、大跨楼盖及体育看台等多种工程结构的重要设计荷载，其随机荷载模型的研究国内外极少。本课题研究步行及跳跃两种典型人致荷载的随机物理模型。首先建立单人步行及跳跃荷载的"质量-弹簧-阻尼器"动力学模型并引入生物力反映运动的物理机制，推导各种典型模型的生物力（激励）与加速度响应（人致荷载）间的频响函数的理论表达式，探讨各模型的适用条件。利用三维动作捕捉和测力鞋垫技术开展步行和跳跃荷载的实验，与已有实验数据一同构建具有代表性的数据库。采用复合反演方法由实验数据识别动力学模型中的参数并研究其概率分布形式。基于实验数据研究生物力的时频域表达形式及控制变量，最终获得步行及跳跃荷载的功率谱表达式，并结合数值模拟技术实现人致荷载的随机模拟。项目研究突破了现象学的研究范式，所提出的功率谱模型可为大跨结构的人致振动舒适度分析、振动控制和可靠性分析等提供荷载基础，为相关设计规范的修订提供依据。

Pedestrian's walking and jumping excitations are very important loads when designing long-span civil structures as footbridge, long-span floor, theatres, sport stadia, structures and factories accommodating vibration-sensitive devices. Investigations on the stochastic model of walking and jumping load, however, are still very limited. This project aims to study the stochastic physical model of walking and jumping load. First, "spring-mass-damper" model (SMD) is established to represent the walking and jumping activity. The frequency response function between the excitation (the biomechanical force inside people) and the response (which is actually the walking load) will be derived for different kinds of SMD models. Applicability of each model will be discussed. Then, walking and jumping test will be conducted on about 150 test subjects using the three-dimensional motion capture technology and insole pressure measurement technology. The experimental data, together with those collected before, will form a good database. The modal parameters of SMD can be identified using the database and their probability distribution property can be investigated. The database will also be employed to study the proper mathematical form for the biomechanical force. Finally, the power spectral model for walking and jumping load can be established. The spectral can be used to simulate walking and jumping time history by numerical simulation method. The proposed stochastic model can be directly used in human-induced structural vibration analysis, vibration control and reliability assessment. Results of this project will lay a sound base for improvement of certain design code.