تحليل احتمالاتي تاثير ماهيت زلزله بر احتمال خرابي سازه ها

Probabilistic analysis of the influence of earthquake nature and content on possibility of structural failure

ﺑﻪ ﺳﺒﺐ وﺟﻮد ﻋﺪم ﻗﻄﻌﯿﺖﻫﺎي ﻓﺮاوان در ﺧﺼﻮﺻﯿﺎت ﺳﺎزه و ﺑﺎرﮔﺬاري، اﺳﺘﻔﺎده از ﺗﺤﻠﯿﻞﻫﺎي ﻣﻌﻤﻮل ﺑﺎ ﺧﻄﺎ ﻫﻤﺮاه اﺳﺖ. در اﯾﻦ ﭘﮋوﻫﺶ ﺑﺮاي رﻓﻊ ﮐﺎﺳﺘﯽ ﯾﺎدﺷﺪه از ﺗﺤﻠﯿﻞ اﺣﺘﻤﺎﻻﺗﯽ اﺳﺘﻔﺎده ﺷﺪ. ﺑﺮاي اﯾﻦ ﮐﺎر، ﺟﻬﺖ ﺑﺮرﺳﯽ اﺣﺘﻤﺎل ﺧﺮاﺑﯽ، ﯾﮏ ﻗﺎب ﺑﺘﻨﯽ ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﺮﻓﺖ و اﯾﻦ ﺳﺎزه ﺗﺤﺖ اﺛﺮ ﭼﻬﺎر زﻟﺰﻟﻪ ﻣﯿﺪان- دور اﻟﺴﻨﺘﺮو، ﻫﺎﭼﯿﻨﻮﻫﻪ، ﮐﺮنﮐﺎﻧﺘﯽ و ﭼﯽﭼﯽ و ﭼﻬﺎر زﻟﺰﻟﻪ ﻣﯿﺪان- ﻧﺰدﯾﮏ ﮐﻮﺑﻪ، ﻧﻮرﺛﺮﯾﺞ، ﮐﺎﯾﻮتﻟﯿﮏ و ﮐﻮآﻟﯿﻨﮕﺎ ﺗﺤﻠﯿﻞ ﮔﺮدﯾﺪ. ﮐﻤﯿﺖﻫﺎي ﻏﯿﺮﻗﻄﻌﯽ ﺳﺎزه از ﻗﺒﯿﻞ ﺟﺮم ﺣﺠﻤﯽ، ﺿﺮﯾﺐ ﮐﺸﺴﺎﻧﯽ و اﺑﻌﺎد ﻫﻨﺪﺳﯽ ﻣﻘﻄﻊ ﺑﺎ ﺳﻪ ﻧﻮع ﺗﻮزﯾﻊ ﯾﮑﻨﻮاﺧﺖ، ﻧﺮﻣﺎل و ﻟﻮگ ﻧﺮﻣﺎل و در ﺿﺮاﯾﺐ ﭘﺮاﮐﻨﺪﮔﯽ ﻣﺨﺘﻠﻒ 5% ، 10% و 15% ﺗﻮﻟﯿﺪ و اﺣﺘﻤﺎل ﺧﺮاﺑﯽ در ﻫﺮ ﺣﺎﻟﺖ ﻣﺤﺎﺳﺒﻪ ﺷﺪ. ﺑﺎ ﺑﺮرﺳﯽ ﻧﺘﺎﯾﺞ ﺑﻪدﺳﺖ آﻣﺪه ﻣﯽﺗﻮان درﯾﺎﻓﺖ ﮐﻪ اﺣﺘﻤﺎل ﺧﺮاﺑﯽ ﺳﺎزه، ﻣﺴﺘﻘﻞ از ﻧﻮع ﺗﻮزﯾﻊ اﺣﺘﻤﺎﻻﺗﯽ ﻣﺘﻐﯿﺮﻫﺎي ﺗﺼﺎدﻓﯽ ﺑﻮده و واﺑﺴﺘﻪ ﺑﻪ ﻣﻘﺪار ﺿﺮﯾﺐ ﭘﺮاﮐﻨﺪﮔﯽ، ﻣﺎﻫﯿﺖ زﻟﺰﻟﻪ از ﻧﻘﻄﻪ ﻧﻈﺮ ﻣﯿﺪان دور و ﻣﯿﺪان ﻧﺰدﯾﮏ و ﺣﺪاﮐﺜﺮ ﺷﺘﺎب زﻟﺰﻟﻪ ﻣﯽﺑﺎﺷﺪ. ﺑﻪ ﻋﺒﺎرت دﯾﮕﺮ، ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ از ﺗﺤﻠﯿﻞ اﺣﺘﻤﺎلاﻧﺪﯾﺸﺎﻧﻪ ﻧﺸﺎن داد ﮐﻪ اﺣﺘﻤﺎل ﺧﺮاﺑﯽ ﺳﺎزه در زﻟﺰﻟﻪﻫﺎي ﻣﯿﺪان- ﻧﺰدﯾﮏ ﺑﺎ ﺿﺮﯾﺐ ﭘﺮاﮐﻨﺪﮔﯽ ﺑﺎﻻﺗﺮ، ﺑﯿﺸﺘﺮ از ﺣﺎﻟﺖ ﻣﺸﺎﺑﻪ در زﻟﺰﻟﻪﻫﺎي ﻣﯿﺪان- دور اﺳﺖ

By studying structural analyses in the space of uncertainty, it is apparent that there has been a little research on the effects of the type of earthquake on probabilistic analysis of the structure with various random distributions and coefficients of variation. Therefore, this research attends to this shortcoming. In order to do so, a one-story steel frame has been used. Structural properties such as density, elastic modulus and beam and column dimensions are considered as uncertain parameters with each having three uniform, normal and log-normal types of density function and three coefficients of variation of 5%, 10% and 15%. This structure excited by two far-field earthquakes (El Centro and Hachinohe), and two near-field ground accelerations (Northridge and Kobe). By applying Monte Carlo simulation method in this research, desired random variables are generated and applied in probabilistic analysis.