Patent ID: 8438795

Claim:
A multi-directional torsional hysteretic damper serving as an anti-seismic device of hysteretic type with multi-directional action for protection of structures against earthquakes characterized in that, it is composed of; at least eight identical yielding cores ( 1 ) each, in the shape of variable-diameter cylinder, which can yield, serving as energy dissipating elements by yielding due to large torsional shear stresses created via arms ( 2 ) welded to them, while the arms rotate back and forth and create torsion in the yielding cores ( 1 ), with each of the yielding cores ( 1 ) having one arm ( 2 ) welded to it at top and with each of the yielding cores being welded to a base plate ( 12 ) at its bottom and maintaining a torsional hinge connection with the plate diaphragm ( 6 ) through the use of core ball bearings ( 3 ) at the yielding cores to ( 1 )—plate diaphragm ( 6 ) connection; a supporting structure composed of supporting column ( 5 ) and the plate diaphragm ( 6 ), the function of which is to support the yielding cores ( 1 ) against bending by taking the major share of the bending moment and thus preventing excessive bending in the yielding cores ( 1 ) which are intended to yield in torsion while being twisted by the rotation of the arms ( 2 ); a rail system comprising identical rails ( 10 ) in the shape of a channel section in the same number as the yielding cores ( 1 ) plus the top plate ( 11 ), with the rails ( 10 ) welded to the top plate ( 11 ) while being positioned parallel to the arms ( 2 ), the function of which are guiding the movement of the arms ( 2 ) at the arm's end points where arm ball bearings ( 4 ) are provided to create, in combination with the rails ( 10 ), a roller hinge type connection between the arm ( 2 ) ends and the bridge deck.