Department of Mechanical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Korea.
J Acoust Soc Am. 2010 Dec;128(6):3507-12. doi: 10.1121/1.3500690.
Several heavyweight impact sources have been used in applying standardized excitation forces to evaluate the noise generation characteristics of building floors. In this study, heavyweight sources (a bang machine and an impact ball) were filmed with a high-speed camera on the period of deformation and restitution of the impact. The generated impact force was measured, and the effects of the taken deforming shapes were investigated. Experimental modal analysis was performed to determine the natural frequencies and mode shapes of the impact sources. With respect to deforming shapes during impacts, the influence of the mode shapes was clearly demonstrated, especially for the impact ball. Using the measured modal properties, the impact force was predicted and compared to the measured excitation force. By comparing the transient variation of the excitation force and its frequency spectrum, the influence of the modal characteristics of the source on the generated impact force was investigated.
已使用几种重型冲击源向建筑地板施加标准化激励力，以评估其噪声产生特性。在本研究中，使用高速摄像机拍摄了重物源（bang 机和冲击球）在冲击变形和恢复期间的变形和恢复过程。测量了产生的冲击力，并研究了所采用的变形形状的影响。进行了实验模态分析，以确定冲击源的固有频率和振型。关于冲击过程中的变形形状，振型的影响得到了清楚的证明，尤其是对于冲击球。利用测量得到的模态特性，可以预测冲击力并将其与测量得到的激励力进行比较。通过比较激励力的瞬态变化及其频谱，可以研究源的模态特性对产生的冲击力的影响。
