تقویت قاب های خمشی بتنی با استفاده از یک میراگر ابتکاری فولادی با مکانیزم برشی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، واحد دره شهر، دانشگاه آزاد اسلامی، دره شهر، ایران.

2 استاد، دانشکده مهندسی عمران، دانشگاه صنعتی شریف

چکیده

< p>میراگرهای غیر فعال انرژی به عنوان ابزار کارا و اقتصادی برای بهبود رفتار لرزه ای سازه ها در برابر بارهای لرزه ای شناخته شده اند. در میان انواع میراگرهای غیرفعال انرژی، میراگرهای فولادی به دلیل سهولت ساخت و اجرا، در دسترس بودن امکانات ساخت آنها، مقرون به صرفه بودن، از مقبولیت بیشتری برخوردار هستند. علاوه بر آن، این نوع میراگرها، عملکرد مطلوبی در مطالعات آزمایشگاهی و عددی، و همچنین در زلزله های گذشته داشته اند. هر چند این نوع میراگرها نسبت به سایر میراگرها اقتصادی تر هستند اما استفاده از آنها در سازه های معمول در مقایسه با سایر سیستم های مرسوم باربر جانبی، اقتصادی نمی باشد. لذا در این مقاله یک میراگر ابتکاری دارای سازوکار تسلیم برشی معرفی شده که از سهولت بالایی در ساخت و اجرا برخوردار بوده و همچنین از جنبه اقتصادی، مقرون به صرفه است. این میراگر پیشنهادی پس از زلزله های شدید براحتی قابل تعویض است. نتایج عددی نشان می دهد که میراگر پیشنهادی باعث بهبود رفتار لرزه ای قاب خمشی بتنی می شود. معمولا افزایش همزمان سختی و شکل پذیری در سازه به راحتی میسر نمی شود اما نتایج نشان می دهد میراگر پیشنهادی باعث افزایش سختی و شکل پذیری سازه می گردد. همچنین با افزایش میرایی در ناحیه غیر خطی باعث اتلاف انرژی اعمالی به سازه می گردد. در این مقاله، روابط لازم برای محاسبه سختی و مقاومت نهایی سیستم و همچنین طراحی آن پیشنهاد شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Strengthening the RC Frames Using an Innovative Steel Damper with Shear Mechanism

نویسندگان [English]

  • Ali Ghamari 1
  • Alireza Khaloo 2
1 1- Department of Civil Engineering, Darreh Shahr branch, Islamic Azad University, Darreh Shahr, Iran.
2 Distinguished Professor, Department Civil Engineering, Sharif University of Technology
چکیده [English]

< p align="center"> 
< p >Passive energy dampers have been identified as efficient and economical tools to improve the seismic behavior of structures against seismic loads. Among all types of passive energy dampers, steel dampers are more popular because of their ease of construction, availability, affordability, economical aspect. In addition, these types of dampers have performed well in the laboratory and numerical studies, as well as in past earthquakes. Although these types of dampers are more economical than other dampers, they are not economical to use in conventional structures compared to other conventional lateral load systems. Therefore, in this paper, an innovative damper with shear mechanism is introduced which is easy to construct and operate and is economical to use. This proposed damper is easily replaceable after severe earthquakes. Numerical results show that the proposed damper improves the seismic behavior of the RC frame. It is usually not easy to increase the stiffness and ductility of the structure at the same time, but numerical results show that the proposed dampers increase the stiffness and ductility of structures. It also causes energy dissipation to the structure by increasing the damping in the nonlinear area. In this paper, the necessary equations for calculating the ultimate stiffness and strength of the system as well as its design are proposed.

کلیدواژه‌ها [English]

  • RC frame
  • Steel Damper
  • Ductility
  • stiffness
  • Seismic Energy
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