برآورد میزان آسیب در اتصالات صلب قاب های خمشی فولادی با استفاده از روش تجزیه متعامد سره و الگوریتم بهینه یابی ازدحام ذرات

نوع مقاله : پژوهشی

نویسندگان

1 دانشجوی دکترا دانشگاه شهید رجائی

2 عضو هیئت علمی

چکیده

یکی از مسائل مهم در شناسائی آسیب سازه ها، تعیین میزان آسیب در اتصالات آنها است. سرعت و دقت در تعیین میزان آسیب، شدیدا به وجود نویز در اندازه گیری پاسخ های سازه بستگی دارد. در این تحقیق روشی پیشنهاد می گردد که با استفاده از آن، دقت و سرعت تعیین میزان آسیب با وجود مقادیر نویز، افزایش می‌یابد. در روش پیشنهادی به جای استفاده از چندین شکل مود طبیعی تنها یک شکل مود متعامد سره استفاده می‌شود و میزان آسیب در اتصالات صلب قاب‌های خمشی با دقت قابل قبولی محاسبه می‌گردد. برای اثبات عملکرد این روش چندین مثال عددی و یک نمونه آزمایشگاهی مطالعه شده‌اند. نتایج نشان می‌دهد که این روش از دقت و سرعت قابل قبولی برای تخمین میزان آسیب در اتصالات صلب قاب‌های خمشی فولادی برخوردار است.

کلیدواژه‌ها


عنوان مقاله [English]

Estimation of damage severity in rigid connection of steel moment frames using the Proper Orthogonal Decomposition and the PSO optimization algorithm

نویسندگان [English]

  • taha teimoori 1
  • Mussa Mahmoudi 2
1 Ph.D. candidate of Structural Engineering, Faculty of Civil Engineering, Shahid Rajaee Teacher Training University-Tehran, Iran.
2 Faculty member
چکیده [English]

One of the most important issues in damage detection is determining the severity of damages. Speed and accuracy in determining the severity of damages depends on the measurement noise. Using the proposed method, damage severity of damaged connections has been calculated in presence of noise, faster and more accurate. In the proposed method, instead of using several natural mode shapes, only first proper orthogonal mode shape is used, and the damage severity of the rigid connections of moment frames is calculated with acceptable accuracy. Several numerical examples and a laboratory model have been studied to prove the performance of this procedure. The results show that this method has acceptable accuracy and speed to estimate the damage severity in the rigid connections of steel moment frames.

The proposed method is based on the finite element model updating method and the objective function is based on the difference between the proper orthogonal decomposition mode shapes of the intact and damaged structure. In the proposed procedure, the wavelet transform is used to reduce the noise in the displacement history of the structure. An optimized image processing method has been used to record structural displacements in the laboratory sample. To optimize the objective function, the particle swarm optimization method has been used. Two numerical scenarios have been studied using the finite element model of a three-story, three-span steel moment frame structure. Also, three laboratory scenarios have been studied on the three-story one-span steel moment frame laboratory model. In this paper, the exact location of the damaged connections are determined using the optimized mode shape curvature difference method. The effects of noise on the accuracy and efficiency of the proposed method are considered. Numerical scenarios have been studied at three noise levels. The proper orthogonal decomposition mode shapes is calculated using the free vibration of the structure under initial displacement.

کلیدواژه‌ها [English]

  • Damage detection
  • Damage severity
  • Proper orthogonal decomposition
  • Particle swarm optimization algorithm
  • Moment frames rigid connection