Enerji sönümleyici çelik yastıklar

The observation on the severely damaged precast concrete industrial buildings after the destructive L'Aquila Earthquake (2009) demonstrated the inadequate seismic performance of connecting elements between cladding panels and other structural elements, which leading to collapse of many panels. Moreover, the cladding walls lack the sufficient energy dissipation capacity, requiring the supplementary energy dissipative component to improve the energy dissipation capability. SAFECLADDING a research study was initiated in the scope of FP7 with collaboration of some European Union universities such as, Istanbul Technical University, Polytechnic University of Milan, University of Ljubljana, National Technical University of Athens, Joint Research Centre - Elsa Laboratory (JRC), and some construction companies from Italy and Turkey, aiming to design the innovative energy dissipative steel connector and to investigate the seismic performance of the Cladding panels equipped with steel connectors. A brand new oval shaped low-cost steel connector was developed in Structural and Earthquake Engineering Laboratory of ITU to be utilized as a connecting element between adjacent panels, panel to beam and panel to support connections of industrial buildings. The experimental and analytical studies were conducted in the scope of this thesis. The experimental studies were performed in two different phases namely; steel cushion tests and system tests. In the first phase, a series of experimental study was performed to investigate the uniaxial and bi-axial behavior of steel cushions with three distinct thicknesses. The high deformation capacity, and high-energy dissipation capability and stable hysteretic curves are the common properties observed from the uniaxial tests. In addition, the performed bi-directional tests showed that the direction of the applied axial load affects the general behavior of the steel cushions, so that with increment of applied compressive axial load the energy dissipation capacity of specimens increase while the relation is inverse in the case of tension type axial load. The interaction curves are plotted for each specific thickness of specimens as well. In the second phase, the system tests were carried out. The testing set up consisted of RC cladding panels and fully pinned swaying steel frame to transfer the lateral load to RC walls. The steel devices were positioned at different locations, in panel to support, in panel to panel between two adjacent panels and in panel to beam connections. In this study, two kinds of test carried out named single cushion test and double cushion test according to the number of steel connector placed as the support per panel. The experimental study was performed to evaluate the energy dissipation capacity and performance of cladding panels equipped with steel devices. The results indicate that the double cushion type tests have higher energy dissipation capacity in comparison with single cushion test type, resulting to appropriate performance of whole system. In the analytical part, the steel cushions are modeled with link elements in the finite element program of SeismoStruct v 6.0. Ramberg-Osgood and asymmetric bi-linear response curves are suggested for modeling of shear and axial behavior of steel cushions analytically as link elements. The mathematical models for system tests are set and experimental and analytical results are compared. In addition force-displacement relation of each steel cushions at different position in the system tests are obtained and their contribution in the energy dissipation capacity are calculated. The results showed that the steel cushions in panel-to-panel and panel to support connections, contribute in the energy dissipation capacity with their shear and axial behavior respectively.