بررسی رفتار سیستم قاب ستون پیوند شده فولادی جهت تقویت قاب‌های بتن‌آرمه

نوع مقاله : مقاله پژوهشی (کاربردی)

نویسنده

استادیار، گروه مهندسی عمران، آموزشکده فنی سمنان، دانشگاه فنی و حرفه‌ای استان سمنان، ایران.

چکیده

یکی از جدیدترین زمینه‌های مطالعات در حوزه مهندسی سازه و زلزله، دستیابی به سیستم‌های سازه‌ای است که پس از وقوع زلزله، به‌سرعت به وضعیت پیش از زلزله و خدمت‌رسانی بازگردد. سیستم قاب ستون پیوند شده فولادی (LCF) یکی از جدیدترین این سیستم‌ها است که با داشتن اعضای تیر پیوند قابل تعویض به‌عنوان عضو فیوز هنگام زلزله از سیستم باربر قائم محافظت می‌کند. پایین بودن زمان، هزینه و سهولت تعمیر در این سیستم‌ها، سبب بازگشت سریع ساختمان به خدمت‌رسانی خواهد شد. در این سیستم، تیرهای پیوند قابل‌تعویض به‌کار رفته، در ابتدا سختی اولیه سیستم را تأمین می‌کنند و سپس با استهلاک انرژی ناشی از تسلیم، رفتار غیرخطی نرم و شکل‌پذیری از خود به نمایش می­گذارند. در این تحقیق، به بررسی رفتار سیستم قاب ستون پیوند شده فولادی برای تقویت قاب­های بتن­آرمه در دو ساختمان پنج و ده طبقه پرداخته ‌شده است. براساس نتایج تحلیل استاتیکی غیرخطی، از دو سازه بتن‌آرمه پنج و ده طبقه تقویت‌شده با سیستم LCF، میزان ظرفیت باربری و قابلیت استهلاک انرژی نسبت به سازه بدون تقویت به‌طور میانگین در حدود 1/3 برابر افزایش می‌یابد؛ به‌طوری‌که مفاصل پلاستیک ابتدا در قاب­های فولادی (LC) تشکیل می­شوند و سازه بتن­آرمه در حالت الاستیک باقی می­ماند. همچنین حداکثر و حداقل مقدار درصد جذب برش برای قاب‌های LC به‌طور متوسط به‌ترتیب در طبقات پایین در حدود 80 درصد و در طبقات بالا در حدود 13 درصد از نیروی زلزله را جذب می­کنند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the behavior of the linked column frame system for retrofitting of the RC frames

نویسنده [English]

  • Alireza Ezoddin
Assistant Professor, Department of Civil Engineering, Faculty of Semnan, Semnan Branch, Technical and Vocational University (TVU), Semnan, Iran.
چکیده [English]

One of the newest fields of study in the field of structural and earthquake engineering is the achievement of structural systems that quickly return to their pre-earthquake state and service after an earthquake. One of the newest of these systems is the Linked Column Frame (LCF) system, which protects the vertical load-bearing system during earthquakes by having the replaceable link beam members as a fuse member. The relative low cost and easy repair process in these systems lead to the rapid return to occupancy after an earthquake. In this system, the replaceable link beams used initially provide the initial rigidity of the system and then exhibit soft nonlinear behavior and ductility with energy dissipation resulting from the yield. In this paper, the behavior of the linked column frame system for retrofitting of the RC frames in two structures of 5- and 10-storeys were investigated. Based on the results of the nonlinear static analysis of the two 5- and 10-storey reinforced concrete structures retrofitted with LCF system, the amount of bearing capacity and the energy dissipation capacity of the structure retrofitted increased by an average of 3.1 times compared to the structures without retrofitting. The plastic hinges were first formed in steel frames (LC frames) and the RC structure remained in an elastic state. Furthermore, the maximum and minimum shear absorption of seismic force percentage of the LC frames were approximately 80% and 13% in the lower and upper storeys, respectively.

کلیدواژه‌ها [English]

  • Linked Column Frame System
  • Link beam
  • Retrofitting
  • plastic hinges formation
  • Shear Absorption Percentage
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