مرکز منطقه ای اطلاع رساني علوم و فناوري - The effect of energy dissipating steel cushions on the behaviour of a typical reinforced concrete frame

Abstract :

Seismic behavior of reinforced concrete frame type structures can be improved by adding energy dissipating metallic devices. Metal devices can dissipate the earthquake input energy by means of plastic deformation when they are located within the bays of the structure. New generation structural design methods tend to concentrate the plastic deformations accumulated on replaceable steel elements rather than on structural members and therefore decrease the damage level. In this study, experimental and analytical investigation was conducted in order to determine the hysteretic behaviour of energy dissipative steel cushion shaped metal elements with variable thicknesses. Shear tests of energy dissipative steel cushions were performed in the Structural and Earthquake Engineering Laboratory (STEELAB) of ITU. Analytical model was developed for the steel cushions and the model was used in the nonlinear analysis of a frame system that was extracted from an actual model structure. The analysis results showed that depending on the thickness, steel cushions increase the strength of the structure in the range of 5% to 20%. 18 mm thick steel cushion instrumented frame dissipates 5 times more energy than the bare frame. Steel cushion having the same thickness dissipated 55% of the total energy of the frame system.