بررسی عملکرد پوشش‌های CFRP و GFRP بر بهبود رفتار استاتیکی غیرخطی اتصالات لوله‌ای X شکل

نوع مقاله : یادداشت پژوهشی

نویسندگان

1 گروه مهندسی عمران، دانشکده فنی، دانشگاه گیلان، رشت

2 گروه مهندسی عمران، دانشکدة فنی، دانشگاه گیلان، رشت

چکیده

در این پژوهش، تأثیرگذاری پوشش‌های FRP (Fiber Reinforced Polymer) بر روی مقاومت نهایی و تغییر شکل اتصالات لوله‌ای X شکل تحت بارگذاری محوری فشاری بررسی‌شده ‌است. برای این هدف، ابتدا نتایج حاصل از مدل‌های المان محدود با نتایج آزمایشگاهی اعتبارسنجی شد. به‌منظور بررسی متغیرهای مختلف در مقاوم‌سازی اتصالات لوله ای X شکل با FRP ازجمله جنس، طول، زاویه دورگیری و تعداد لایه ­ها، 75 اتصال در حالت­ های تقویت‌شده و تقویت‌نشده ایجاد و تحلیل شدند تا رفتار استاتیکی غیرخطی آن­ها موردمطالعه قرار گیرد. در این مدل‌‌ها، تماس بین لایه‌های FRP و اعضای فلزی در نظر گرفته‌شده است، همچنین پروفیل جوش در محل تقاطع عضو اصلی با عضوهای فرعی مدل‌سازی شده است. نتایج نشان داد که نحوه قرارگیری این پوشش‌ها روی اتصال و اندازه طول آن‌ها روی عضو اصلی، تأثیر محسوسی بر روی بهبود عملکرد اتصال دارند. همچنین این پوشش‌ها می‌توانند مقاومت نهایی اتصال را تا 125 درصد افزایش و جابه‌جایی‌ها را تا 84 درصد کاهش دهند.

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of the Performance of CFRP and GFRP Wraps on Improving the Nonlinear Static Behavior of Tubular X-Joints

نویسندگان [English]

  • Pooya Rezadoost 1
  • Hossein Nassiraei 2
  • Seyed Ahmad Neshaei 2
1 Department of Civil Engineering, Faculty of Engineering, University of Guilan, Rasht, Iran.
2 Department of Civil Engineering, Faculty of Engineering, University of Guilan, Rasht, Iran
چکیده [English]

Tubular structures are made of hollow steel members with circular cross-sections and connecting them is one of the major challenges in their design. So far, some techniques to improve the performance of tubular connections have been proposed. Most of these methods can only be used for structures during the fabrication, but there are only a few techniques that can be applied during both fabrication and operation. Due to the successful experience of using composite materials for the repair and retrofitting of structures, special attention has now been paid to examining the efficacy of these materials in offshore structures.
In this research, the effect of CFRP and GFRP wraps on the ultimate strength and deformation of tubular X-joints under compressive load is investigated. For this purpose, the results of the finite element (FE) models were validated with several available experimental tests. After that, the nonlinear static behavior of tubular X-joints strengthened with FRP was studied. In these FE models, the contact between the FRP layers and the steel members (chord, weld, and braces) was considered. Also, the weld profile in the brace/chord intersection was modeled.

کلیدواژه‌ها [English]

  • Tubular X-joint
  • Axial compression
  • FRP wraps
  • Finite element method
  • Ultimate strength
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