The major objective of this study is experimentally and theoretically to investigate the characteristics of rectangular Tuned Liquid Damper (TLD) under wave excitation. An obvious engineering motivation for this study is to explore the applicability of TLDs for suppressing the structural vibration of offshore platforms. The structural model used to perform experiments is scaled according to a full size platform by matching their dynamic properties. Rectangular TLDs of different sizes and water depths are examined. By observing the performance and the behavior of TLDs through laboratory experiments, the study investigates the influence of a number of parameters. In an analytical or numerical study, a mathematical model that describes the nonlinear behavior of liquid in TLD and the interaction of TLD and structure is prerequisite. Validity of the mathematical models to simulate the behavior of liquid in TLD and TLD-structure interaction has been evaluated based on the experimental results.
Being similar to a Tuned Mass Damper (TMD) in concept, a TLD imparts indirect damping to the system and thus improves structural performance. The TLD absorbs structural energy by means of viscous actions of the fluid and wave breaking. To date, the TLD technique has been successfully applied to suppress the vibration of onshore buildings under wind or seismic loadings (Bauer, 1984; Fuiino, et al., 1988; Sun, et al., 1989: Welt and Mode, 1989; Wakahara, et al, 1992; Tamula, et al, 1995; Yeh, et al., 1996; Reed et al., 1998). It seems that this technique offers one promising option to reduce the vibration of offshore structures under wave loading. The maior objective of this study is experimentally and theoretically to investigate the characteristics of TLDs under wave excitation. An obvious engineering motivation for this study is to explore the applicability of TLD for suppressing the structural vibration of offshore platforms.
