Document Type : Original Research Paper


1 Assistant Professor, , Faculty of Civil Engineering, Khajeh Nasir Tusi University of Technology,Tehran,Iran

2 Faculty of Civil Engineering, Khajeh Nasir al-Din Tusi, Industrial University,Tehran,Iran


Considering the purpose of Regulation 2800, which is to ensure the safety of life at risk level 1, as well as the progress made in the design method based on the performance and development of new design regulations, in this study, asymmetric steel structures in one In order to have a coaxial brace that is designed according to the 2800 standard of the third edition and the tenth issue of the national regulations, from the perspective of design, based on the performance and criteria of the Iran Improvement Instruction, Do or not. For this purpose, 12 steel buildings with coaxial brace system in groups of 5, 8, 11 and 14 floors are analyzed and studied by leaving the centers of difficulty compared to the center of mass 0, 10 and 20%, which is due to the displacement of braces in one direction. At the stage of performance appraisal, the results of static and dynamic nonlinear analysis of buildings, including relative displacement of floors, determination of structural performance point, paste deformations of compressive and tensile braces, and ratio of force to column capacity with acceptance, comparison and level criteria. The performance of buildings and their components has been determined. The results show that regular and irregular structures of 11 and 14 floors provide the level of life safety performance at risk level 1. This is almost true of 8-story structures, but in 5-story structures, especially in the symmetrical direction, weaknesses have been observed that need to be addressed to ensure the level of safety of the lifeguard.


Main Subjects

[1] Ghobarah Ahmed،" Performance-Based Design in Earthquake Engineering:State of Development", Engineering Structures, Vol 23, 2001, pp 878-884,. [ و 2] ،   ﻣﺮﻛــﺰ ﺗﺤﻘﻴﻘــﺎت ﺳــﺎﺧﺘﻤﺎن ﻣــﺴﻜﻦ " آﻳــﻴﻦ ﻧﺎﻣــﻪ   ﻃﺮاﺣــﻲ ﺳــﺎﺧﺘﻤﺎن ﻫــﺎ در ﺑﺮاﺑــﺮ زﻟﺰﻟــﻪ: 2800 اﺳــﺘﺎﻧﺪارد )ﺳﻮم وﻳﺮاﻳﺶ ( " 1384.  [3] FEMA 273,"NEHRP Guideline for the  seismic Rehabilitation of Buildings", Federal     Emergency Management Agency (FEMA) , Wshington D.C.,USA, 1996. [4] Collins Kevin R.,Chen Potuan, "Some Observations on Performance-Based and Reliability-Based Seismic Design of Asymmetric Building Structures", Engineering Structures, Vol 23, 2001, pp1005-1010.  [5] M.N.Bugeja,D.P.Thambiratnam,G.H.Brameld, "The influence of stiffness and strength eccentricities on the inelastic earthquake response of asymmetric structures", Engineering Structures,Vol 21, 1999, pp856863. 
]6[ ، ﻣﺮﻛﺰ ﺗﺤﻘﻴﻘﺎت ﺳﺎﺧﺘﻤﺎن وﻣﺴﻜﻦ "
ﺣﺪاﻗﻞ ﺑﺎر وارد 
ﺑﺮﺳﺎﺧﺘﻤﺎن ﻫﺎ واﺑﻨﻴﻪ ﻓﻨﻲ:
519 اﺳﺘﺎﻧﺪارد
" 1379.  
[ و 7] دﻓﺘﺮﺗﺪوﻳﻦ  ﺳﺎﺧﺘﻤﺎن ﺗﺮوﻳﺞ ﻣﻘﺮرات ﻣﻠﻲ "
دﻫﻢ ﻣﻘﺮرات ﻣﻠﻲ ﺳﺎﺧﺘﻤﺎﻧﻲ اﻳﺮان:
ﻃﺮح واﺟﺮای 
ﺳﺎﺧﺘﻤﺎﻧﻬﺎی ﻓﻮﻻدی " 1376.  [ وﻣﻬﻨﺪﺳﻲ 8] ﭘﮋوﻫﺸﮕﺎه ﺑﻴﻦ اﻟﻤﻠﻠﻲ زﻟﺰﻟﻪ ﺷﻨﺎﺳﻲ   زﻟﺰﻟﻪ " دﺳﺘﻮراﻟﻌﻤﻞ ﺑﻬﺴﺎزی ﻟﺮزه ای ﺳﺎﺧﺘﻤﺎن ﻫﺎی ﻣﻮﺟﻮد "    .1381ﺧﺮدادﻣﺎه ]9[   ﭘﮋوﻫﺸﮕﺎه ﺑﻴﻦ اﻟﻤﻠﻠﻲ زﻟﺰﻟﻪ ﺷﻨﺎﺳﻲ وﻣﻬﻨﺪﺳﻲ زﻟﺰﻟﻪ " ﺗﻔﺴﻴﺮدﺳﺘﻮراﻟﻌﻤﻞ ﺑﻬﺴﺎزی ﻟﺮزه ای ﺳﺎﺧﺘﻤﺎن ﻫﺎی ﻣﻮﺟﻮد "    .1381ﻣﻬﺮﻣﺎه ]10[  ﻣﺴﻌﻮد ﻣﺮادی" ﺑﺮرﺳﻲ ﺳﻄﺢ ﻋﻤﻠﻜﺮد ﺳﺎزه ﻫﺎی ﻓﻮﻻدی ﻧﺎﻣﺘﻘﺎرن در ﻳﻚ ﺟﻬﺖ ﻃﺮاﺣﻲ  ﺷﺪه  ﺑﺮ ﺳﻮم 2800 اﺳﺎس اﺳﺘﺎﻧﺪارد وﻳﺮاﻳﺶ "  ﭘﺎﻳﺎن ﻧﺎﻣﻪ ﻛﺎرﺷﻨﺎﺳﻲ ارﺷﺪ داﻧﺸﮕﺎه ﺧﻮاﺟﻪ ﻧﺼﻴﺮ اﻟﺪﻳﻦ ﻃﻮﺳﻲ، 1385.