فهرست:
فصل 1: مقدمه.............................................................................................................................................................................................................. 7
1-1-مقدمه................................................................................................................................................................................................................ 8
فصل 2: مروری بر ادبیات موضوع................................................................................................................................................................ 13
2-1-مقدمه............................................................................................................................................................................................................ 14
2-2-روش طراحی لرزه ای بر اساس روش تجویزی.................................................................................................................. 15
2-2-1-عوامل مؤثر بر ضریب کاهش نیروی زلزله............................................................................................................... 18
2-2-1-1-شکل پذیری................................................................................................................................................................. 18
2-2-1-1-1-ضریب شکل پذیری کلی سازه........................................................................................................... 19
2-2-1-1-2-ضریب کاهش بر اثر شکل پذیری.................................................................................................... 20
2-2-1-2-مقاومت افزون............................................................................................................................................................. 25
2-2-1-2-1-ضریب مقاومت افزون............................................................................................................................... 27
2-2-2-شکل پذیری در روش طراحی براساس روش تجویزی.................................................................................... 29
2-3-روش طراحی لرزهای براساس عملکرد سازه........................................................................................................................ 30
2-3-1-فواید طراحی براساس عملکرد......................................................................................................................................... 31
2-3-2-شکلپذیری در روش طراحی براساس عملکرد..................................................................................................... 32
2-3-3-معیارهای پذیرش اعضا در روش طراحی براساس عملکرد........................................................................... 34
2-3-4-فلسفه ی طراحی براساس عملکرد............................................................................................................................... 35
2-4-مروری بر یافته های دیگر محققین.......................................................................................................................................... 36
2-4-1-تحقیقات طاهری بهبهانی.................................................................................................................................................. 36
2-4-2-تحقیقات Repapis و همکاران................................................................................................................................... 37
2-4-3-تحقیقات Kunnath و همکاران................................................................................................................................ 38
2-4-4-تحقیقات Elnashai و همکاران.................................................................................................................................... 39
2-5-جمع بندی و نتیجه گیری............................................................................................................................................................. 40
فصل 3: روش تحقیق............................................................................................................................................................................................ 42
3-1-مقدمه............................................................................................................................................................................................................ 43
3-2-معرفی نمونه ها....................................................................................................................................................................................... 43
3-2-1-تعیین جزئیات سازه ای...................................................................................................................................................... 44
3-2-1-1-مدلسازی و هندسه.................................................................................................................................................. 44
3-2-1-2-بارگذاری......................................................................................................................................................................... 45
3-2-1-3-نتایج طراحی نمونه ها............................................................................................................................................ 48
3-3-ارزیابی........................................................................................................................................................................................................... 50
3-3-1-مدلسازی....................................................................................................................................................................................... 50
3-3-1-1-مدلسازی کلی سازه................................................................................................................................................ 50
3-3-1-2-مدلسازی اعضا............................................................................................................................................................ 51
3-3-1-3-مدلسازی رفتار مصالح........................................................................................................................................... 52
3-3-1-4-مقاومت اعضای سازهای...................................................................................................................................... 52
3-3-1-5-بررسی منحنی رفتاری اعضاء........................................................................................................................... 53
3-3-2-بررسی نرم افزارهای کاربردی......................................................................................................................................... 54
3-3-3-بررسی مشخصه های تحلیل نمونه ها........................................................................................................................ 54
3-3-3-1-روش تحلیل.................................................................................................................................................................. 54
3-3-3-2-بارگذاری......................................................................................................................................................................... 55
3-3-3-2-1-الگوی بارگذاری........................................................................................................................................... 56
3-3-3-3-تغییر مکان هدف...................................................................................................................................................... 56
فصل 4: نتایج و تفسیر......................................................................................................................................................................................... 61
4-1-مقدمه............................................................................................................................................................................................................ 62
4-2-بررسی نتایج.............................................................................................................................................................................................. 63
4-2-1-بررسی نتایج و تعیین ضرایب نمونه سه طبقه....................................................................................................... 66
4-2-2-بررسی نتایج و تعیین ضرایب نمونه پنج طبقه...................................................................................................... 69
4-2-3-بررسی نتایج و تعیین ضرایب نمونه هفت طبقه................................................................................................... 72
4-2-4-بررسی نتایج حاصل از شکل پذیری سازه............................................................................................................... 72
4-3-تعیین عملکرد لرزهای اعضاء......................................................................................................................................................... 74
4-3-1-عملکرد لرزهای اعضا در ساختمان سه طبقه....................................................................................................... 79
4-3-2-عملکرد لرزهای اعضا در ساختمان پنج طبقه...................................................................................................... 84
4-3-3-عملکرد لرزهای اعضا در ساختمان هفت طبقه................................................................................................... 89
فصل 5: جمع بندی و نتیجه گیری............................................................................................................................................................ 90
5-1-جمع بندی................................................................................................................................................................................................ 91
منابع و مراجع........................................................................................................................................................................................................... 95
منبع:
ABSTRACT
The Philosophy of the new generations and retrofitting codes, which are on the basis of performance based approaches rather than the prescriptive methods of current codes, has brought about diverse method in desighn. An understanding of the seismic behavior of structure to provide a proper performance level has a significant role in the modern design methods. Consequently, investigating the reliability of the existing factors in these codes seems essential.
In this paper, the ductility reduction factor (effective on R-factor) given in 2800 standard is compared to the correspondent facrors, like the ductility factor of members (m-factor) given in the guideline of seismic rehabilitation of existing buildings. In order to fulfill this research three steel framed buildings which their lateral load resisting system are moderate steel frame with CBF bracing are modeled analyzed using nonlinear static procedure. The R-facrors resulted from analyses are compared to the given values in 2800 standard and their correlation with ductility factors of members are extracted. The results of these evaluations are recommended to estimate, revise and adjust the current factors of codes and standards.
Key Word: performance level, behavior factor, ductility factors of members, structure ductility.