تحلیل احتمالاتی نشست آنی شالوده‌ی مستطیلی بااستفاده از نرم‌افزار‌های مختلف قابلیت اعتماد

نوع مقاله : پژوهشی

نویسندگان

• هادی فتاحی
• فاطمه جیریانی شراهی
• سام مهرنیا

دانشکده‌ی مهندسی علوم زمین، دانشگاه صنعتی اراک.

10.22067/civil.v33i3.88206

چکیده

بررسی نشست در پی‌های سطحی با برعهده داشتن وظیفه‌ی انتقال نیروهای سازه به زمین، یکی از عوامل مهم در طراحی سازه‌ها می‌باشد. پارامترهای خاک به‌دلیل ماهیت غیرهمگن آن، دارای عدم قطعیت‌های زیادی هستند که صرف نظر کردن از آن‌ها در تخمین میزان نشست، ایراداتی را در تحلیل پایداری سازه وارد می‌کند. ازاین‌رو، امروزه استفاده از روش‌های قابلیت اعتماد با توانایی پذیرفتن عدم قطعیت‌ها و تحلیل پایداری مورد اطمینان مسائل ژئوتکنیکی، مورد استقبال قرار گرفته‌اند. در این تحقیق به‌منظور تخمین احتمال شکست ناشی از نشست آنی یک شالوده‌ی مستطیلی سطحی، از روش‌های مرتبه اول و مرتبه دوم قابلیت اعتماد و هم‌چنین شبیه‌سازی مونت‌کارلو کمک گرفته شد و تحلیل‌های مربوط به آن در نرم‌افزارهای RT و @Risk انجام شد. نتایج به‌دست‌آمده، حاکی از بالا بودن احتمال شکست مربوط به نشست شالوده (۵/۹٪) است. روش‌های مرتبه دوم و شبیه‌سازی مونت‌کارلو به‌دلیل خطی نبودن رویه‌ی حالت حدی، نتایج دقیق‌تری را ارائه می‌دهند. به‌علاوه تحلیل حساسیت متغیرهای تصادفی براساس بردارهای اهمیت نشان داد که بار وارد شده بر شالوده نقش مهمی در احتمال شکست دارد و پس از آن ضریب پواسون متغیرتصادفی بااهمیتی است.

کلیدواژه‌ها

• احتمال شکست
• نرم‌افزار RT
• نرم‌افزار @Risk
• نشست پی‌های سطحی

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عنوان مقاله [English]

Probabilistic Analysis of Immediate Settlement of a Rectangular Foundation Using Various Reliability Software

نویسندگان [English]

• Hadi Fattahi
• Fateme Jiryaee
• Sam Mehrnia

Rock Mechanics, Department of Earth Sciences Engineering, Arak University of Technology, Arak, Iran.

چکیده [English]

Study of immediate settlement of a rectangular foundation with the task of transferring structural forces to the ground, is one of the important factors in the design of structures. Due to its heterogeneous and anisotropicnature, soil parameters have highuncertainties, the omission of which in estimating the settlement of foundation, creates challenges in the analysis of structural stability. Therefore, the use of reliability methods with the ability to accept uncertainties and reliable stability analysis of geotechnical issues are welcomed today. In this study, in order to estimate the probability of failure due to settlement of rectangular foundation, first-order and second-order reliability methods as well as Monte Carlo simulations were used and the relevant analysis were performed in RT and @Risk software.The results indicate a high probability of failure related to the foundation settlement (9.5%). The second-order methods and Monte Carlo simulations provide more accurate results due to the non-linearity of the limit state procedure. In addition, the sensitivity analysis of random variables based on sensitivity vectors showed that thecontact stress (q_o), has an important role in the probability of failure, and then the Poisson’s ratio is important.

کلیدواژه‌ها [English]

• Probability of failure
• RT software @
• Risk software
• Surface foundations meeting

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