Abstract
The dynamic characteristics of a nine-story SRC building were investigated using incident waves generated from impactor machine. It is shown that this device can be right tool to investigate the vibration characteristics of the actual building up to relatively high frequencies range. Horizontal motions as well as rocking and torsional motions were investigated. The pulse like generated wave makes it possible to observe later arrival torsional response, which cannot be obtained in microtremor and vibration test using vibrator. To clarify the modal variations, mode decomposition analysis has been done.