Structural damping includes material damping, friction effects at bearing and expansion joints, friction at bolted joints and mechanical damping by damper. There is not analytical basis for estimating the damping ratios. Structural damping ratios can be estimated by measuring forced vibration amplitude of a certain mode but it is almost impossible to vibrate the actual bridges to a certain mode by force. Therefore, RD technique utilizing a lot of ambient vibration data can be a practical method to estimate damping ratio. In this study, the damping ratio is estimated by analyzing the ambient vibration data of three steel cable stayed bridges.

• 이덕근(한국시설안전공단, 특수교유지관리센터, 공학박사) | Lee, Deok Keun
• 김인호(한국시설안전공단, 특수교유지관리센터, 공학박사) | Kim, In Ho
• 유동우(한국시설안전공단, 특수교유지관리센터, 공학박사) | Yoo, Dong Woo
• 홍성수(한국시설안전공단, 특수교유지관리센터, 공학박사) | Hong, Seong Soo
• 마상수(한국시설안전공단, 특수교유지관리센터, 공학박사) | Ma, Sang Soo