Performance assessment of tuned liquid column dampers under random seismic loading

The performance of tuned liquid column dampers (TLCDs) for the passive control of flexible structures under random seismic loading is investigated using random vibration analysis. A non-stationary stochastic process with frequency and amplitude modulation is used to represent the earthquake strong motion, and an equivalent linearization technique is used to account for the non-linear damping force in the TLCD. The TLCD performance is evaluated on the basis of the structural response statistics, namely, the expected maximum and root-mean-square displacements, and root-mean-square absolute accelerations and interstory shears. Illustrative examples are presented using SDOF and MDOF shear-beam structural models, and two stochastic input ground motions representing short-duration and long-duration ground motions with low frequency content. A parametric study is conducted to investigate the effects of the mass ratio, coefficient of head loss for the damper, and loading intensity on the TLCD performance.