Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 2001: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2000: ¥1,600,000 (Direct Cost: ¥1,600,000)
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Research Abstract |
Tainter gates (radial gates) are frequently used as a crest gate of dam for a flood release. A huge Tainter gate installed on Folsom dam in Califrnia, induced vibrations and failed, early in the morning of July 17, 1995. Apossibility that vibration participated in its failure was pointed out from just after the accident, and some failure analysis studies have been performed by applicants In this study, field vibration tests were conducted on a 47-ton full-scale gate under practical uses, to determine its in-air and in-water natural vibration characteristics. Experimental modal tests, using an impact hammer and accelerometers, were conducted on the gate, thus addressing its in-air natural frequencies, mode shapes and modal damping. Subsequently, the in-water vibration tests were conducted to reveal the vibration characteristics of the gate. Conclusively, comparison of the calculated inherent in-water vibration frequency and the measured frequency of the in-water self-excited vibration confirms the validity of the theoretical analysis developed for full-scall gate
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