Tunable Tuned Liquid Column Dampers with Multi Cells for Wind Vibration Control of Tall Buildings

Tuned liquid column damper (TLCD) is used to reduce wind induced building acceleration by tuning its natural frequency to that of a building. After building construction, its natural frequency may differ from the original one. Thus, TLCD installed at a building should have the shifted natural frequency without its serious structural modification. Conventional TLCD changes its natural frequency by only regulating liquid height, which destroys U shape of TLCD. This study proposes new concept of TLCD which yields wide range of natural frequency with very simple modification maintaining original shape. Vertical columns of TLCD are divided into several individual cell type small columns. The liquid in individual cell type columns cannot move by air pressure if their tops are sealed. By taking appropriate number of cell type columns in sealed condition, sectional area ratio of vertical and horizontal columns is changed, which can provide new natural frequency same to shifted natural frequency of a building. TLCD's with multi cells are analytically evaluated and experimentally verified using shaking table test according to the number of sealed cell type small columns.