Optimum absorber parameters for tuned liquid column dampers

Tuned liquid column dampers (TLCDs) are a class of tuned liquid dampers tha t impart indirect damping to the primary structure through oscillations of the liquid column in a U-shaped container. The energy dissipation in the wa ter column results from the passage of the liquid through an orifice with i nherent head-loss characteristics. The overall damping in a TLCD depends on the head-loss coefficient and the velocity of the oscillating liquid, and it is nonlinear due to the quadratic damping term. Using the TLCD theory an d the equivalent linearization scheme, a new approach has been developed th at helps to compute the optimum head-loss coefficient for a given level of wind or seismic excitation in a single step, without resorting to iteration s. The optimal damping coefficient and tuning ratio of a TLCD using a singl e degree of freedom system under the white noise and a set of filtered whit e noise excitations representing wind and seismic loadings is presented. Op timum values of damping have also been investigated for multiple TLCDs. An example is presented to demonstrate the performance of multiple TLCDs in co ntrolling multiple modes under wind excitation.