Forced vibration testing of footbridges using calibrated human shaker and wireless sensors
Forced vibration testing of footbridges using calibrated human shaker and wireless sensors
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DOI：
10.1016/j.proeng.2017.09.134
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
J. Brownjohn;M. Bocian;D. Hester
中科院分区：
文献类型：
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作者：
J. Brownjohn;M. Bocian;D. Hester
为生物力学应用设计的无线惯性测量单元（伊穆斯）已被评估用于土木结构的模态测试，特别是人行桥，其中小尺寸和高响应水平与传感器能力相匹配。基于对直接使用跑步机或测力板的步行和跳跃中的地面反作用力（GRF）的恢复的研究，已经发现单个仔细定位的IMU可以在全尺寸结构上的开放空间条件下成功地恢复GRF。的GRF的第一和第二谐波的振幅可以恢复一致的和小的偏置误差乘以解决的垂直分量加速度由身体mass.of许多潜在的应用，一个直接使用的是能够进行强迫振动试验，而无需机械激励。所需要的是记录结构的加速度沿着人的跳跃，以便在结构的固有频率处产生强的谐波分量。虽然在识别振型和满足相关系统识别程序的要求方面存在一些问题，但该程序已成功应用于两座截然不同的行人天桥。本文介绍了这两座桥梁的施工过程和结果。
Wireless inertial measurement units (IMUs) designed for biomechanical applications have been evaluated for modal testing of civil structures, in particular footbridges, where the small size and high response levels match the sensor capabilities. Building on research into recovery of ground reaction forces (GRFs) in walking and jumping directly using a treadmill or force plate, it has been found that a single carefully located IMU can successfully recover GRFs in open space conditions on full-scale structures. Amplitudes of first and second harmonics of the GRFs can be recovered with consistent and small bias errors by multiplying resolved vertical component acceleration by body mass.Of the many potential applications, one with immediate use is the ability to carry out forced vibration tests without mechanical excitation. All that is needed is to record the acceleration of a structure along with that of a human jumping so as to generate a strong harmonic component at the structure’s natural frequency. There are caveats involving identification of mode shape and satisfying requirements of the relevant system identification procedure, but the procedure has been applied successfully to two very different footbridges. The procedure and the results for these two bridges are described in the paper.