Impact of aftershocks on steel structures

Historical earthquakes have shown that large earthquakes are often followed by repeated aftershocks, and They form a series of earthquakes and aftershocks. In most structures damaged by earthquakes due to the intervalShort-term aftershocks cannot be repaired. In such cases, strong aftershocks may occur. They can increase the level of damage to structures with new failures. Earthquakes may cause weakness, or Collapse of structures that were previously damaged (but not yet repaired) under the main earthquake. In this dissertation, 3 5-story steel structures with bending frames with irregularities of 0, 20 and 40% were first designed with the help of ETABS software and then with the help of Abaqus finite element software, a 3D frame with structural details. Designed and modeled. In order to investigate the effect of aftershocks on the structure, 3 stages of analysis are performed on the frame