This paper presents a study on wind-induced torsional vibration control of long span bridges by using tuned liquid column damper (TLCD). First, the governing equations for a bridge-TLCD system are derived with considering ail the three displacement components of the deck in vertical. lateral, and torsional vibrations. The interactions between the bridge deck, the TLCD, the aeroelastic forces, and the aerodynamic forces are fully reflected in the governing equations. Then, buffeting analysis is carried out through random vibration approach. And then, a critical nutter condition is identified from nutter analysis. Finally, a numerical example is presented to illustrate the effectiveness of the tuned liquid column damper in suppressing Mind-induced torsional buffeting response and in increasing critical flutter wind velocity of a long span suspension bridge. It is concluded that the TLCD can be an effective device for wind-induced vibration control or long span bridges.
