Abstract
This study evaluated the vibration use and safety of students living in the dormitories on the 12th and 14th floors by feeling uncomfortable. The measurement method was to measure the acceleration due to free vibration and single - person walking. The slab stiffness was then calculated, and the usability and safety were compared according to international standards. The natural frequency of the slab was 6.8 Hz. The natural frequency of a typical slab is around 15Hz. Therefore, the evaluation slab is judged as a flexible floor structure. It is considered that there is a high possibility of resonance in the middle of daily life because of low natural frequency and near harmonic component of walking vibration. As a result, the RMS acceleration level is within the tolerance range defined by ISO 10137 code, but the 13th floor exceeds the reference limit, so that a sensitive person could detect the vibration somewhat in the lying position.