Efficiency of a tuned liquid column damper considering a seismic excitation of low frequency content and uncertainty

Abstract

In this research the behaviour of a linear structure controlled by a tuned liquid column damper (TLCD) subjected to stochastic seismic excitations of low frequency content is analysed. To accommodate the non-linear nature of TLCD, an equivalent statistical linearization is performed. The behaviour of the optimal TLCD design parameters, frequency ratio and pressure loss coefficient, when entering uncertainty in system parameters, is studied. The parameters considered were the mass ratio, the length ratio and the pressure drop coefficient. The optimization objective is to reduce the standard deviation of the displacement of the structure. The effect of the inclusion of uncertainty in the parameters, in the reduction of the displacement of the structure, and in the root mean square RMS of the displacement of the structure is analysed. It is found that an uncertainty in the mass ratio, and in the TLCD length ratio, does not produce variations in the efficiency or in the RMS of displacement of the structure. However, an uncertainty in the value of the period of the structure produces large variations in the efficiency and the RMS of the displacement of the structure.