مطالعه آزمایشگاهی اثر محصورشدگی فعال الیاف آرامید بر عملکرد لرزه‌ای ستون‌های بتن مسلح تحت اثر هم‌زمان بارهای محوری و جانبی

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی عمران، واحد تهران غرب، دانشگاه آزاد اسلامی، تهران، ایران

10.22124/jcr.2023.21068.1533

چکیده

یکی از راهکارهای مناسب تقویت سازه‌های بتنی افزایش محصورشدگی بتن است. بتن محصورشده با الیاف پلیمر آرامید (AFRP) دارای رفتار مناسبی ازنظر افزایش ظرفیت باربری سازه و شکل‌پذیری است. استفاده از عامل محصورشدگی فعال در اعضای بتنی باعث بهبود عملکرد آن‌ها تحت نیروی فشاری می‌شود. در این تحقیق نتایج بررسی رفتار ستون‌های بتن مسلح دارای محصورشدگی فعال با استفاده از نوارهایی با جنس الیاف AFRP تحت اثر مشترک بار فشاری محوری و بار جانبی رفت و برگشتی ارائه می‌گردد. علاوه بر این ستون‌ها، از یک ستون بدون محصورشدگی (SCR) به‌عنوان نمونه شاهد استفاده‌شده است. نتایج این پژوهش گویای آن است که ستون‌های دارای محصورشدگی فعال در مقایسه با ستون‌ شاهد به دلیل جلوگیری از اتساع بتن و فشار به وجود آمده توسط نوارهای مجزای الیافی، ازنظر مقاومت فشاری تا 21 درصد و انرژی الاستیک تجمعی تا 125 درصد بهبود می‌یابند، لذا می‌توان از این روش در تقویت ستون‌های بتن مسلح استفاده کرد..

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental study on the effect of active confinement of AFRP fibers on the seismic performance of reinforcement concrete columns under axial and lateral loads

نویسندگان [English]

  • shahla Jeddian
  • Mohammad Ghazi
  • mehdi esfandi sarafraz
Department of Civil Engineering, West Tehran Branch, Islamic Azad University, Tehran, Iran
چکیده [English]

Fiber Reinforced Polymers (FRP) are often used for structural repairs to improve the strength and ductility of the structures. Previous studies have shown that utilizing active confinement in concrete structures can improve the seismic behavior of concrete columns under pressure. In this study, the behavior of concrete columns actively confined by AFRP fibers was investigated under the combined effects of axial compressive and cyclic lateral loads. Two concrete columns were actively confined by AFRP strips. In addition, a non-confined column (SCR) was utilized as a control specimen. Then all specimens were tested under axial and lateral cyclic loading. Experimental results showed that the ultimate compressive strength and axial strain of specimens with active confinement are improved compared to the SCR specimen. Also, due to the increased number of small cracks in the specimen, a higher extent of energy was absorbed under the applied loading. The loading protocol caused no rupture in the AFRP strips, and no shear crack and brittle failure in the specimens were observed.

کلیدواژه‌ها [English]

  • Active confinement
  • Polyamide polymer fibers
  • Seismic performance
  • Ductility

مراجع

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