Research Of A Brace-type Visco-plasic Damper

The energy-dissipated structure refers to installment dampers, which can dissipatethe seismic energy, so, the response of structure under earthquake or wind vibraion isinduced. A new brace-type visco-plastic damper is introduced in this paper, It consist ofdouble pre-bent metallic strips, tube, supports and viscoelastic materials. Doublepre-bent metallic strips is symmetry, located in the central of the tube; the supports fixedon the strips, support to the tube; viscoelastic material filled between the tube and thestrips. When the damper spread or shorten in axial direction, the pre-bent strips shrinkor expand in transverse direction, the viscoelastic materials inside is deformed anddissipate energy. When the damper experience large deformation, the pre-bent stripyielding and dissipate energy also. The tube prevent stiffness of the damper excessivedecreases in compression. To prevent local buckling of the pre-bent strips, manysupports could set inside the tube.Parametric analyses are performed using finite element software (ABAQUS).During the parametric analyses, the following behavior of the damper is investigated,such as hysteresis behavior, amount of energy dissipated by plastic deformation andamount of energy dissipated by viscoelastic materials. The performance of the damper isinvestigated under different load frequencies and different displacement amplitudes.The effects of the damper for frame structure and the behavior of the damper isinvestigated. Elasto-plastic time history analyzing method is used, the results shows thatthe damper plays a important role for frame in shock absorption, such as, the top floordisplacement and the story displacement of the frame with damper is greatly induced.Whether little or big seismic vibration, the damper dissipate major energy of total inputenergy in the structure. Under low levels of vibration, the damper dissipates energy through the deformation of viscoelastic material. under strong levels of vibration, thedamper dissipate energy is added through the plastic deformation of pre-bent strips.