بهینه‌سازی طراحی قاب بتن‌آرمه خورده شده با استفاده از الگوریتم ژنتیک

نوع مقاله : علمی - پژوهشی

نویسنده

گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه شهید مدنی آذربایجان، تبریز، ایران

چکیده

در این مطالعه یک رویکرد ساده شده برای بهینه‌سازی طراحی قاب بتن‌آرمه با ملاحظه اثرات خوردگی ناشی از نفوذ یون کلراید ارائه شده است. تابع هدف در بهینه‌سازی قاب کمینه‌سازی وزن آن بوده و بهینه‌سازی با استفاده از الگوریتم ژنتیک انجام خواهد یافت. قیود مسئله بهینه‌سازی به صورت عدم فراگذشت لنگر خمشی تیرها و نیروی محوری ستونها از مقادیر مقاوم متناظر و همچنین عدم فراگذشت مقدار دریفت بیشینه قاب از مقدار مجاز دریفت آیین‌نامه‌ای تنظیم می‌شوند. به منظور ملاحظه اثرات خوردگی، قاب بتن‌آرمه 5 طبقه در دو نقطه زمانی مختلف صفر و 50 سال در عمر سرویس‌دهی آن مورد بهینه‌سازی قرار گرفته است. نقطه زمانی صفر نشان دهنده قاب سالم خورده نشده است. در ادامه تحلیل نمونه‌گیری به روش مونت کارلو در نرم‌افزار Rt برای تخمین زمان شروع خوردگی با ملاحظه عدم‌قطعیت‌های درگیر در مسئله استفاده شده است. بر اساس زمان شروع خوردگی بدست آمده، در نقطه زمانی 50 سال سطح مقطع آرماتورهای فولادی مقاطع تیرها و ستون‌ها ناشی از اثر خوردگی کاهش داده شده‌اند. چارچوب پیشنهاد شده برای بهینه‌سازی قاب در نرم‌افزار MATLAB پیاده‌سازی شده و برای تعیین پاسخ سازه در حین فرآیند بهینه‌سازی از تحلیل استاتیکی خطی سازه توسط نرم‌افزار OpenSees استفاده شده است. نتایج نشان دهنده کارایی روش پیشنهاد شده برای بهینه‌سازی طراحی قاب‌های بتن‌آرمه با ملاحظه اثر خوردگی در طول عمر مفید آن است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Design Optimization of Corroded Reinforced Concrete Frame using Genetic Algorithm

نویسنده [English]

  • Mohammadreza Seify Asghshahr
Department of Civil Engineering, Faculty of Technology and Engineering, Azarbaijan Shahid Madani University, Tabriz,, Iran
چکیده [English]

In this study, a simplified approach is proposed for design optimization of the reinforced concrete frame considering the effects of chloride-induced corrosion. The objective function is to minimize the frame weight, and optimization will be conducted utilizing the genetic algorithm. The constraints of the optimization problem are set in a manner that bending moment of beams and axial force of columns are not exceeding the respective resistant values, and the maximum drift of the frame is not exceeding the code-defined allowable drift. In order to examine the corrosion effects, a 5-story reinforced concrete frame is optimized in two different time points 0 and 50 years in its service life. The zero time point indicates the sound uncorroded frame. Monte Carlo sampling method in Rt software is utilized to estimate the corrosion initiation time incorporating the involved uncertainties. At time point of 50 years, a cross-sectional area of steel bars in beam and column sections is reduced due to the corrosion effects. The proposed framework for the frame optimization is implemented in MATLAB software; and for computing the structural response during the optimization process, the linear static analysis of the structure in OpenSees software is conducted. Results indicate an ability of the proposed framework for design optimization of reinforced concrete frames considering the corrosion effects in their service life.

کلیدواژه‌ها [English]

  • Optimization
  • Reinforced Concrete Frame
  • Chloride-induced Corrosion
  • Genetic Algorithm
  • MATLAB Software
  • OpenSees Software
  • Rt Software
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