The purpose of this study is to get a more precise frequency of hollow core slabs by comparing the observed values from the actual free vibration tests and the predicted values based on the analysis model. The actual free vibration tests were carried out in the construction field using Ω shaped hollow core slabs. Modal analysis is conducted based on the analysis model that takes into account the differences in section properties due to void parts of slab. The differences between the predicted values based on the modal analysis with analysis model and the measured data from the actual tests range from 2~7%. This study demonstrates that the analysis model that incorporates void parts of slab could be used in evaluating serviceability of hollow core slabs with reasonable accuracies.

Abstract
 1. 서 론
 2. 진동계측 및 분석
  2.1 가진실험 및 계측
  2.2 실험결과 및 분석
 3. 모드해석
  3.1 중공 단면에 따른 단면 2차모멘트 산정
  3.2 중공단면에 따른 질량변화 검토
  3.3 모드해석 결과
 4. 결 론
 References

• 강경수(동명대학교 건축공학과 부교수) | Kyoung-Soo Kang Corresponding author