The relationship between time-varying eccentricity of load with the corner lateral displacement response of steel structure during an earthquake

  • Takin, Kambiz (Department of Civil Engineering, Science and Research Branch, Islamic Azad University) ;
  • Hashemi, Behrokh H. (Structural Engineering Research Center (SERC), International Institute of Earthquake Engineering & Seismology (IIEES)) ;
  • Nekooei, Masoud (Department of Civil Engineering, Science and Research Branch, Islamic Azad University)
  • Received : 2015.02.25
  • Accepted : 2015.12.10
  • Published : 2016.03.20


In an actual design, none of the structures with shear behaviors will be designed for torsional moments. Any failure or damages to roofs, infills, shear walls, and braces caused by an earthquake, will inevitably result in relocation of center of mass and rigidity of the structure. With these changes, the dynamic characteristics of structure could be changed during an earthquake at any moment. The main objective of this paper is to obtain the relationship between time-varying eccentricity of load and corner lateral displacement. In this study, various methods have been used to determine the structural response for time-varying lateral corner displacement. As will be seen below, some of the structural calculation methods result in a significant deviation from the actual results, although these methods include the interaction effects of modes. Controlling the lateral displacement of structure can be performed in different ways such as, passive dampers, friction dampers, semi-active systems including the MR damper and active Systems. Selecting and locating these control systems is very important to bring the maximum safety with minimum cost into the structure. According to this study will be show the relation between the corner lateral displacements of structure and time-varying eccentricity by different kind of methods during an earthquake. This study will show that the response of the structure at the corners due to an earthquake can be very destructive and because of changing the eccentricity of load, calculating the maximum possible response of system can be carried out by this method. Finally, some kind of systems must be used for controlling these displacements. The results shows that, the CQC, DSC and exact methods is comply each other but the results of Vanmark method is not comfortable for these kind of buildings.


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