The purpose of this study is to estimate the thickness of concrete slabs using the impact echo method based on the stress waves, which is one of the nondestructive test method, to evaluate the safety and construction conditions of concrete slabs. If the correlation and reliability of the impact echo method and the slab thickness are secured, it can be considered that the quality control of the concrete slab is possible in existing structures and structures under construction.

Abstract
 1. 서 론
 2. 충격반향기법
 3. 실험계획 및 방법
 4. 실험결과 및 고찰
 5. 결 론

• 홍성욱(한밭대학교 도시건축재생기술연구소, 한양대학교 건축학부) | Hong, Seong-Uk
• 윤상기(한밭대학교 건축공학과) | Yoon, Sang-Ki
• 김종현(한밭대학교 건축공학과) | Kim, Jong-Hyun
• 김승훈(한밭대학교 건축공학과) | Kim, Seung
• 이용택(한밭대학교 건축공학과) | Lee, Yong-Taeg 교신저자