Moving orifice circular liquid column damper for controlling torsionally coupled vibration

The effectiveness of the Tuned Liquid Column Damper (TLCD) has been established in controlling the vibration of structures from wind or earthquakes. The present study demonstrates the effectiveness of the Circular Liquid Column Ball Damper (CLCBD), in conjunction with the Tuned Liquid Column Ball Damper (TLCBD) in controlling torsionally coupled vibration of building subjected to wind excitations. Unlike TLCDs, these devices are equipped with moving orifice, implemented via steel balls, placed at the middle of the liquid tube. The set of equations of motion of the combined structure-damper system are derived using the Lagrange's approach. The optimal performance is ensured through selection of optimal parameters by minimization the stochastic responses, obtained from random vibration analysis. This is in order to adequately take care of the stochastic excitations. The optimal performances are further verified in respect to the time history responses under simulated wind excitations. Parametric studies are conducted to assess the performance robustness. The proposed TLCBD-CLCBD system offers enhanced control efficiency and significant reduction of the displacement of liquid column than the TLCD. Experimental investigation using Shake table test facility also corroborate with the findings from the analysis.