بررسی رفتار اتصالات جوش شده فولادی نیمه گیردار بر رفتار لرزه ای قاب‌های فولادی سه بعدی

ﻧﻈﺮ ﺑﻪ اﯾﻨﮑﻪ ﻗﺎب ﻫﺎی ﺧﻤﺸﯽ ﻓﻮﻻدی ﺑﺎ اﺗﺼﺎل ﮔﯿﺮدار ﯾﮑﯽ از ﺳﯿﺴﺘﻢﻫﺎی ﻣﻘﺎوم در ﺑﺮاﺑﺮ ﺑﺎرﻫﺎی ﺟﺎﻧﺒﯽ ﻣﺎﻧﻨﺪ زﻟﺰﻟﻪ و ﺑﺎد ﻫﺴﺘﻨﺪ، ﻧﻘﺶ ﻣﻘﺎوﻣﺖ اﺗﺼﺎل در اﯾﻦ ﻗﺎبﻫﺎ ﻧﻘﺶ ﺣﯿﺎﺗﯽ ﺧﻮاﻫﺪ ﺑﻮد. اﺗﺼﺎل اﺳﺘﺨﻮاﻧﯽ ﯾﮑﯽ از اﺗﺼﺎﻻت ﻣﺪرن ﮔﯿﺮدار ﺟﻮﺷﯽ اﺳﺖ، ﮐﻪ ﭘﺲ از زﻟﺰﻟﻪ ﻫﺎی دو دﻫﻪ اﺧﯿﺮ ﻣﻮرد ﺗﻮﺟﻪ ﻃﺮاﺣﺎن ﺳﺎزه ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. در اﯾﻦ ﭘﮋوﻫﺶ ﺑﻪ ﺑﺮرﺳﯽ ﻧﻮﻋﯽ از اﺗﺼﺎل ﻧﯿﻤﻪ ﺻﻠﺐ اﺻﻼح ﺷﺪه ﻣﻨﺎﺳﺐ ﺟﻬﺖ ﺗﺨﻤﯿﻦ ﻣﯿﺰان ﺟﺬب اﻧﺮژی اﯾﻦ ﻧﻮع اﺗﺼﺎﻻت ﭘﺮداﺧﺘﻪ ﺷﺪه اﺳﺖ. از ﻧﺘﺎﯾﺞ ﺑﺮﻣﯽآﯾﺪ ﮐﻪ ﺑﺎ ﮐﺎﻫﺶ ﺗﻌﺪاد ﻃﺒﻘﺎت ﺳﺎزه، ﺷﮑﻞﭘﺬﯾﺮی ﺳﺎزهﻫﺎ ﮐﺎﻫﺶ ﯾﺎﻓﺘﻪ و ﺑﺎ اﻓﺰاﯾﺶ ﺷﮑﻞﭘﺬﯾﺮی ﺳﺎزهﻫﺎ ﻣﯽ ﺗﻮان ﺑﻪ درﯾﻔﺖﻫﺎی ﺑﺎﻻﺗﺮی در ﺳﺎزهﻫﺎ، در ﯾﮏ ﺳﻄﺢ زﻟﺰﻟﻪ ی زﻟﺰﻟﻪ ﯾﮑﺴﺎن دﺳﺖ ﯾﺎﻓﺖ. ﺑﻪ ﻋﺒﺎرﺗﯽ ﺑﺎ اﻓﺰاﯾﺶ ﺻﻠﺒﯿﺖ اﺗﺼﺎﻻت، ﺳﺎزه دارای رﻓﺘﺎر ﺻﻠﺐﺗﺮی ﻣﯽﺑﺎﺷﺪ و ﻧﯿﺰ ﺳﺎزهﻫﺎی دارای ﺷﮑﻞﭘﺬﯾﺮی ﺑﯿﺸﺘﺮ، در ﺳﻄﺢ ﺷﺪت ﻟﺮزهای ﭘﺎﯾﯿﻦﺗﺮی اﻓﻘﯽ ﻣﯽﮔﺮدﻧﺪ و ﺳﺎزهﻫﺎی ﺻﻠﺐﺗﺮ در ﺳﻄﺢ ﺑﺎﻻﺗﺮی ﻗﺮار ﻣﯽﮔﯿﺮﻧﺪ ﮐﻪ در ﻧﺘﺎﯾﺞ ﺗﺤﻠﯿﻞ اﺳﺘﺎﺗﯿﮑﯽ ﻏﯿﺮﺧﻄﯽ ﻧﯿﺰ ﻧﻤﻮد ﭘﯿﺪا ﮐﺮده اﺳﺖ و ﺑﺎ ﮐﺎﻫﺶ ﺻﻠﺒﯿﺖ اﺗﺼﺎﻻت، زﻣﺎن ﺗﻨﺎوب ﻣﻮﺛﺮ ﺳﺎزه ﻧﺎﻣﺘﻘﺎرن اﻓﺰاﯾﺶ ﻣﯽﯾﺎﺑﺪ و ﺷﺘﺎب ﻃﯿﻔﯽ ﮐﺎﻫﺶ ﻣﯽﯾﺎﺑﺪ. ﻫﻤﭽﻨﯿﻦ ﻧﺸﺎن داده ﺷﺪه اﺳﺖ ﮐﻪ اﺗﺼﺎل rbs ﺗﺎﺛﯿﺮ ﮐﻤﯽ در ﻗﺴﻤﺖ ﺧﻄﯽ ﻣﻨﺤﻨﯽﻫﺎ دارد وﻟﯽ ﺑﺎ اﻓﺰاﯾﺶ درﯾﻔﺖﻫﺎ، ﮐﺎﻫﺶ اﺿﺎﻓﻪ ﻣﻘﺎوﻣﺖ ﺳﺎزه ﻗﺎﺑﻞ ﺗﻮﺟﻪ اﺳﺖ. اﯾﻦ ﻧﻮع اﺗﺼﺎل ﺑﺎﻋﺚ اﻓﺰاﯾﺶ ﺗﻘﺎﺿﺎی ﺗﻐﯿﯿﺮﺷﮑﻠﯽ در ﻣﻔﺎﺻﻞ ﺗﯿﺮﻫﺎ ﻣﯽﮔﺮدد. اﻓﺰاﯾﺶ ﺿﺮﯾﺐ رﻓﺘﺎر در اﺗﺼﺎل ﺑﺎ ﺟﺎن ﮐﺎﻫﺶ ﯾﺎﻓﺘﻪ ﻧﺴﺒﺖ ﺑﻪ اﺗﺼﺎل ﻣﻌﻤﻮﻟﯽ ﺑﯿﺸﺘﺮ اﺳﺖ و ﺑﺎ ﮐﺎﻫﺶ ﺻﻠﺒﯿﺖ اﺗﺼﺎﻻت، درﺻﺪ ﻣﺸﺎرﮐﺖ ﻣﻮدﻫﺎی ﺑﺎﻻﺗﺮ اﻓﺰاﯾﺶ ﯾﺎﻓﺘﻪ ﺑﻨﺎﺑﺮاﯾﻦ در ﺳﺎزهﻫﺎی دارای اﺗﺼﺎﻻت ﻧﯿﻤﻪ ﺻﻠﺐ ﺗﻌﺪاد ﻣﻮدﻫﺎی ﻣﻮﺛﺮ در ﺳﺎزه ﻧﺴﺒﺖ ﺣﺎﻟﺖ ﺻﻠﺐ ﺑﯿﺸﺘﺮ اﺳﺖ. اﯾﻦ ﻣﻮﺿﻮع در ﻃﺮاﺣﯽ ﺳﺎزه ﻧﻘﺶ ﻣﻬﻤﯽ اﯾﻔﺎ ﻣﯿﮑﻨﺪ. ﻟﺬ ا ﻫﻤﺎﻧﻄﻮر ﮐﻪ از ﻧﺘﺎﯾﺞ اﯾﻦ ﭘﮋوﻫﺶ ﺑﺮﻣﯽآﯾﺪ، در ﮐﺎرﻫﺎی ﮐﻤﯽ ﻣﯽ ﺗﻮان ﺑﺮرﺳﯽ ﻫﻤﻪ ﺟﺎﻧﺒﻪ اﯾﻦ روش را در ﮐﺸﻮر ﻣﺸﺎﻫﺪه ﻧﻤﻮد ﭼﺮاﮐﻪ ﺗﺎ ﮐﻨﻮن ﺑﺮرﺳﯽ در راﺳﺘﺎی ﻣﻮﺿﻮع اﯾﻦ ﭘﮋوﻫﺶ ﺻﻮرت ﻧﭙﺬﯾﺮﻓﺘﻪ اﺳﺖ.

Investigation of the behavior of semi-conductive welded steel joints on seismic behavior of 3D steel frames

Given that bent steel bending frames are one of the loadresisting systems such as earthquakes and winds, the role of bonding resistance in these frames will be crucial. The purpose of this study was to investigate the behavior of semiconductive welded steel joints on the seismic behavior of 3D steel frames. The results of this study show that with the decrease in the number of structural classes, in this project the reduced formability of the structures decreases the IDA curves to a lower IM level, indicating that with increasing Structural plasticity can be achieved by higher computations in structures at the same earthquake level. Also, the coating curves corresponding to the structures with less ductility are at a higher level, that is, the coating curve is lower at higher level, with increasing formability in nonlinear static analysis. In other words, with increasing rigidity of the joints, the structures behave more rigidly and their bending curves are higher and the structures with higher plasticity become horizontal at lower seismic intensity levels. And the rigid structures are at a higher level, which is also reflected in the results of nonlinear static analysis, and by decreasing the rigidity of the joints, the effective alternation time of the asymmetric structure increases and the spectral acceleration decreases. Also with decreasing joint rigidity, the contribution of higher modes increased, so in semirigid joints the number of effective mods in the structures is higher than the rigid state. This issue can play an important role in the design of the structure. According to the findings of this study, little work can be done to investigate this method in the country, although research on the behavior of welded steel joints has so far been studied.