RESONANT VISCOUS DAMPING DEVICE FOR EARTHQUAKE-RESISTANT STRUCTURES

DESIGNERS CAN REDUCE EARTHQUAKE DAMAGE TO BUILDINGS IN ONE OF THREE WAYS: INCREASED STRENGTH, BASE ISOLATION, OR DAMPING. DAMPING ELEMENTS ARE AN ATTRACTIVE OPTION FOR FLEXIBLE FRAME BUILDINGS. RESEARCHERS ARE DESIGNING A NEW TYPE OF PASSIVE DAMPING MECHANISM THAT IS POTENTIALLY SUPERIOR TO CONVENTIONALDAMPING MECHANISMS: A RESONANT VISCOUS DAMPER, OR RVD. THE RVD IS BEING PLACED IN THE SAME LOCATIONS AS CONVENTIONAL EARTHQUAKE DAMPERS, BUT OFFERS MUCH HIGHER LEVELS OF PASSIVE DAMPING. THE RVD IS A PRACTICAL, RELIABLE, ECONOMICAL DEVICE THAT CAN BE APPLIED TO A BROAD RANGE OF MEDIUM-SIZE BUILDINGS. THE RVD CONCEPT IS BEING VALIDATED BY BOTH ANALYSIS AND TESTING. CURRENT EARTHQUAKE DAMPERS ARE DESIGNED TO PROVIDE 20-30 PERCENT STRUCTURAL DAMPING. THE RVD PROVIDES OVER TWICE THIS DAMPING IN THE PRIMARY MODE OF A BUILDING WITHOUT ANY LARGE INCREASES IN FRAME STIFFNESS NOR ANY LARGE ADDED MASSES. IT ALSO REDUCES MOTION DUE TO WIND SWAY. AN RVD OFFERS DESIGNERS IN ANY FIELD OF STRUCTURAL DYNAMICS (CIVIL, AEROSPACE, MECHANICAL) AN ATTRACTIVE ALTERNATIVE SOLUTION TO ANY VIBRATION SUPPRESSION PROBLEMS.