ارزیابی رفتار قاب های خمشی بدون خاموت در هسته اتصال و بهسازی شده با روش بزرگنمایی هسته اتصال

نوع مقاله : مقاله پژوهشی

نویسنده

استادیار، گروه مهندسی عمران، واحد سمنان، دانشگاه آزاد اسلامی سمنان

10.22124/jcr.2023.23940.1614

چکیده

بسیاری از سازه‌های قاب خمشی بتن‌آرمه موجود دارای جزئیات نامناسب در آرماتورگذاری بوده که باعث مشکلاتی همچون ظرفیت تغییر مکان جانبی کم، قابلیت استهلاک انرژی پائین، زوال مقاومت و بروز مکانیزم در محل‌های نامطلوب در سازه می‌گردد. یکی از این مشکلات، ضعف در مقاومت برشی هسته اتصال بواسطه عدم آرماتورگذاری عرضی در هسته اتصال می باشد. لذا هدف این مقاله بررسی رفتار قاب های بهسازی شده با استفاده از نبشی سخت شده و میله های پس کشیده می باشد. در این مطالعه پس از انجام مطالعه آزمایشگاهی بر روی دو نمونه اتصال کنترلی و بهسازی شده و صحت سنجی رفتار اتصالات کنترلی و بهسازی شده با استفاده از نرم افزار Opensees اقدام به مدلسازی قاب های 4و8 طبقه گردیده و اثر شیوه بهسازی در رفتار جانبی انها بررسی شده است. نتایج مطالعات حاکی از بهبود رفتار قاب های بهسازی شده در زمینه شکل پذیری، مقاومت و استهلاک انرژی می باشد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Evaluation of the behavior of moment frames without stirrup in the joint core and improved by the method of enlargement of the joint core

نویسنده [English]

  • ali golafshar
Assistant Professor, Department of Civil Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran
چکیده [English]

Many of the existing reinforced concrete structures have inappropriate details in the reinforcement, which causes problems such as low lateral displacement capacity, low energy consumption, strength deterioration, and occurrence of mechanisms in undesirable places in the structure. One of these problems is the weakness in the shear resistance of the joint core due to the lack of transverse reinforcement in the joint core. In this research, the effect of using the method of enlarging the joint core in improving the behavior of joints without transverse reinforcements in the joint core has been investigated. For this purpose, after conducting experimental studies on the control and improved connections and validating their numerical model, the control and improved concrete frames of 4 and 8 stories have been modeled in OpenSees software, and their lateral behavior has been analyzed using non-linear static analyzes under Uniform lateral loading and incremental cyclic loading were compared and evaluated. The results of the studies indicate the use of the studied improvement method in connections stirrups in the core increases the bearing capacity, reduces pinching, increases energy disipation and forms a flexural hinge in the beam.

کلیدواژه‌ها [English]

  • Beam-column connection
  • Seismic improvement
  • Cyclic behavior
  • Pushover analysis
  • Numerical simulation

مراجع

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