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Minimization of torsional oscillation of multi-storey asymmetrical RC buildings by placement of Special Anti-seismic Steel

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: / . , , , . , . /, (....). , . , . , , .... . ABSTRACT: How a RC multistory building behaves and reacts on an earthquake very much depends on the dimensions and the topology of the stiffening elements of the building. Lack of symmetry on certain building causes significant torsional oscillation which in turn results in failure of structural elements mostly on the perimeter of the buildings. All modern regulations take this torsional asymmetry of the buildings into consideration and introduce special and more detailed analyses and calculation procedures to face it. This paper investigates the possibility reducing the possible torsion of such asymmetrical multistory RC buildings by introducing Special anti Seismic Steel Elements (SaSSEs) at pre-selected locations. For the purpose of selecting of the performance characteristics of the SaSSEs, a procedure based on the ultimate postelastic displacements is being utilized. 1 . , , ..., email: paniko@civil.auth.gr 2 . , , ..., email: fgravala@civil.auth.gr

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Antonucci R., Balducci F., Castellano M., Ahmadi H., Goodchild I. and Fuller K. (2003),

Seismic Retrofit of an Existing School Building by Means of Viscoelastic Dampers, Fifth National Conference on Earthquake Engineering, 26-30 May, Istanbul, Turkey.

Bergman, D. M., and Goel, S.C., (1987), Evaluation of Cyclic Testing of Steel-Plate Devices for Added Damping and Stiffness, Report UMCE, 87-10, Dept. of Civil Eng., Univ. of Michigan, Ann Arbor.

14

CEN Eurocode 8 (2004), Design of structures for earthquake resistancePart 1, General rules, seismic actions and rules for buildings, Brussels.

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. . (1996), , 12 , , , . 295 - 305.

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