بررسی اتصال پیش تنیده FRP به بتن با روش شیار زنی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه صنعتی اصفهان، دانشکده مهندسی عمران

2 دانشگاه صنعتی اصفهان

3 هیات علمی گروه عمران دانشگاه صنعتی اصفهان

10.22124/jcr.2024.26203.1636

چکیده

در مقاوم سازی سازه‌های بتن آرمه با ورق‌های تقویتی FRP، توجه به جدا شدگی زود رس ورق تقویتی از سطح بتن امری مهم و ضروری است. از جمله راه کارهای کاربردی در به تعویق انداختن جدا شدگی و استفاده‌ی کاراتر از مصالح می‌توان به استفاده از FRP پیش تنیده اشاره نمود. استفاده از FRP پیش تنیده مزایای مختلفی از جمله افزایش ظرفیت کلی عضو سازه‌ای، افزایش بار ترک خوردگی و کاهش نیرو در آرماتورها دارد. از طرفی در سال‌های اخیر محققین نشان داده‌اند که روش‌های شیار زنی می‌تواند تا حد مطلوبی پدیده‌ی جدا شدگی را به تعویق اندازد. بنابراین در این تحقیق با به کار گیری روش‌های شیار زنی در تقویت با ورق‌های FRP پیش تنیده، عملکرد اتصال ورق به بتن مورد بررسی قرار می‌گیرد. نتایج حاصل از آزمایش برش مستقیم-اتصال پیش تنیده نشان داد که استفاده از گروه شیار 15@5 با پیش تنیدگی 20 و 30 درصد، منجر به افزایش مقاومت اتصال به ترتیب به میزان 146 و 195 درصد نسبت به نمونه‌ی مبنا می‌شود. در واقع استقاده‌ی هم زمان از تقویت خارجی با FRP پیش تنیده و روش‌های شیار زنی موجب عملکرد بسیار مطلوب سطح اتصال خواهد شد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Investigation of prestressed FRP joint via Grooving Method

نویسندگان [English]

  • ٍErfan Shabani 1
  • Alireza Saljoughian 2
  • Davood Mostofinejad 3
1 Civil Engineering Department,- Isfahan University of technology
2 Isfahan university of technology
3 Isfahan university of technology
چکیده [English]

In the strengthening of RC structures with fibre-reinforced polymer (FRP) sheets, it is crucial to prevent the premature deboning of the FRP composites from the concrete surface. One effective method for delaying debonding and enhancing material usage is the use of pre-stressed FRP composites. This technique provides several benefits, such as increasing the overall capacity of the structure, enhancing cracking capacity, reducing strain in the longitudinal rebars, and etc. Recent research has demonstrated that grooving methods can effectively delay the debonding. Consequently, this study investigates the bond behavior between concrete and prestressed FRP sheets strengthened using grooving methods. The results from the lap shear-prestressed test revealed a substantial increase in performance when using the 5@15 groove class with 20% and 30% prestressing. In comparison to the reference specimen, there was an increase of 146% and 195%, respectively. This indicates that the utilization of prestressed FRP with grooving methods can significantly enhance bond capacity.

کلیدواژه‌ها [English]

  • Lap shear -prestressed test
  • prestressed FRP composites
  • bond behavior
  • externally bonded reinforcement method
  • externally bonded reinforcement on grooves method

مراجع

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[21] http://www.sika.com.
[22] http://www.quantomEPR3301.co.uk.

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