بررسی آزمایشگاهی و تحلیلی تیرهای بتن مسلح تقویت شده با پلیمرهای مسلح الیافی و مواد پایه سیمانی مسلح الیافی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، دانشکده مهندسی، دانشگاه فردوسی مشهد، مشهد، ایران

2 گروه مهندسی عمران ،دانشکده مهندسی، دانشگاه فردوسی مشهد ،مشهد

10.22124/jcr.2022.21288.1540

چکیده

هدف از پژوهش حاضر مقایسه بین تیرهای تقویت شده با پلیمرهای مسلح الیافی (FRP) و مواد پایه سیمانی مسلح الیافی (FRCM) می‌باشد. بدین منظور شش تیر بتن مسلح ساخته شده و با FRP و FRCM تقویت گردیدند. همچنین پارامترهای دیگری مانند نوع روش تقویت و مقدار میلگرد خمشی نیز مورد بررسی قرار گرفت. نتایج نشان می‌دهد که در روش تسلیح خارجی (EBR)، تقویت با FRCM منجر به افزایش ظرفیت باربری در مقاطع با مقدار میلگرد خمشی و به ترتیب به میزان 8/12 درصد و 8/16 درصد در مقایسه با تقویت با FRP می‌گردد. همچنین مود گسیختگی تیرهای تقویت شده با روش EBR، در تقویت با FRP به صورت جداشدگی ورق FRP و در تقویت با FRCM به صورت پارگی شبکه FRCM می‌باشد. در روش تسلیح خارجی بر روی شیار (EBROG)، ظرفیت باربری تیرهای تقویت شده با FRP و FRCM تقریباً مشابه یکدیگر می‌باشد. همچنین مود گسیختگی مشاهده شده در روش EBROG برای تقویت با FRP و FRCM به ترتیب به صورت جداشدگی بخشی از پوشش بتن و جداشدگی کامل پوشش بتن روی میلگردهای کششی می‌باشد. در نهایت نتایج آزمایشگاهی با روابط آیین‌نامه‌ها و مدل‌های تحلیلی موجود مورد بررسی قرار گرفت. نتایج نشان داد که با افزایش مقدار میلگرد خمشی در تیرهای تقویت شده با FRP، ظرفیت باربری به دست آمده از روابط آیین‌نامه‌ها و مدل‌های تحلیلی به ظرفیت باربری آزمایشگاهی نزدیک‌تر می‌گردد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental and analytical investigation of RC beams strengthened by FRP and FRCM

نویسندگان [English]

  • Javad Sabzi 1
  • Mohammad Reza Esfahani 2
1 Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
2 Department of Civil Engineering, Faculty of Engineering, Ferdowsi University Of Mashhad (FUM)
چکیده [English]

The present study aims to compare the flexural behavior of reinforced concrete (RC) beams strengthened by fiber reinforced polymer (FRP) with that of fiber reinforced cementitious matrix (FRCM) sheets. Accordingly, 6 RC beams were manufactured and strengthened by FRP and FRCM. Other parameters such as strengthening method and tensile reinforcement ratio were investigated. The results show that in externally bonded reinforcement (EBR) method, strengthening by FRCM sheets leads to the improvement of load carrying capacity by 12.8% and 16.8%, respectively, in specimens with and compared to the specimens strengthened by FRP sheets. Furthermore, the failure mode of specimens strengthened by EBR method was debonding in case of FRP sheets while the failure mode of FRCM strengthened specimens was fiber rupture. In externally bonded reinforcement on grooves (EBROG) method, the load carrying capacity of specimens strengthened by FRP and FRCM was almost the same, while their failure mode was debonding with partial cover separation and complete cover separation. Finally, the experimental results were compared to the existing models and different code provisions. It was observed that by increasing the tensile reinforcement ratio in FRP strengthened beams, the predicted results by analytical models become closer to the experimental results.

کلیدواژه‌ها [English]

  • beam
  • reinforced concrete (RC)
  • fiber reinforced polymer (FRP)
  • fiber reinforced cementitious matrix (FRCM)
  • strengthening

مراجع

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