We have identified the subway of structures as subway station users complained of vibrations from a structures when they walked through middle stairs of escalator. As a result of converting the vibration level to the conversion rate, it was measured at 3.846mm/s(82.7dB) on the B1st floor and 0.966mm/s(70.7dB) on the B2nd floor. These results are higher than the domestic standard of 65dB and lower than the international standard of under 5mm/s. It is felt well with the human body, but the structure is considered to be harmless. Therefore, it is deemded the structure is safe to usue. As the result of measuring the national frequency, the stairs on the B1st floor to be 3.01Hz and the stairs B2nd floor to be 5.36Hz. We consider that the users feel discomfort and anxiety on the B1st floor, where displacement and vibrations are higher.

• 권영정(한국시설안전공단 교량터널안전실) | Kweon, Young Jung
• 박광림(한국시설안전공단 교량터널안전실) | Park, Gwang rim
• 곽길호(한국시설안전공단 교량터널안전실) | Kwak, Kil Ho
• 길태형(한국시설안전공단 교량터널안전실) | Gil, Tae Hyung
• 백남철(한국시설안전공단 교량터널안전실) | Back, Nam Cheol