In Korea, inspection and precise safety diagnosis is regularly carried out to maintain and manage the main tunnel(NATM) which has been passed ten years after completion. In this study, we collected the laboratory test results of the concrete lining in the existing road and railway tunnels, and analyzed the correlation between compressive strength and unit mass of concrete. It is hoped that it will be used for efficient maintenance and management work of tunnels in the future.

Abstract
 1. 서 론
 2. 시험방법
 3. 실내시험 결과분석
 4. 결 론
 참고문헌

• 이태형(한국시설안전공단) | Lee, Tae Hyung 교신저자
• 이태형(한국시설안전공단) | Park, Kyung Han
• 이승율(한국시설안전공단) | Lee, Seung Yul
• 황인백(한국시설안전공단) | Hwang, In Baek