Optimization of tuned liquid column dampers

The effectiveness of a tuned liquid column damper (TLCD) in controlling structural vibration is studied. A numerical method is adopted to account for nonlinearity of the governing equation. Optimum parameters of the TLCD for maximum reduction of peak structural response to harmonic excitations in a wide frequency range are presented for a wide range of flexible structures. A variation of U-shaped TLCD with different cross-sectional areas in its vertical and horizontal sections is investigated. It is found that an increase in cross-sectional area ratio (vertical/horizontal) can greatly reduce the length requirement of a TLCD making it more attractive to flexible structures. A new type V-shaped TLCD is also investigated. This type of TLCD can suppress stronger vibrations such as those caused by strong wind. It is found that, like the tuned mass damper (TMD), there is an optimum tuning ratio (damper frequency/structure frequency) for maximum reduction in response of a structure system which is independent of the excitation. The optimum coefficient of head loss will depend on the intensity of the excitation with smaller coefficient of head loss associated with stronger excitation.