بهینه‌سازی تقویت ستون‌های بتن‌آرمه با مقطع مستطیلی توسط ورق‌های FRPبه روش دورپیچ

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه آزاد اسلامی واحد خمینی شهر

2 دانشگاه آزاد اسلامی خمینی شهر دانشکده مهندسی عمران

چکیده

دورپیچ نمودن ستون بتن‌آرمه توسط ورق‌های FRP باعث افزایش مقاومت فشاری بتن می‌شود. منحنی تنش- کرنش بتن محصور شده توسط FRP با منحنی تنش-کرنش بتن معمولی متفاوت است؛ لذا از روابطی که آئین‌‍‌‌نامه‌ها جهت طراحی و آنالیز ستون بتن‌آرمه‌ی معمولی (تقویت نشده) ارائه نموده‌اند و مبتنی بر منحنی تنش-کرنش بتن معمولی است، نمی‌توان برای آنالیز و طراحی ستون تقویت شده توسط FRP استفاده نمود. در این تحقیق در ابتدا با استفاده از منحنی تنش-کرنش بتن محصور شده که توسط محققین و آیین‌نامه‌ی ACI ارائه شده است، الگوریتمی برای تعیین ظرفیت محوری و خمشی ستون تقویت شده طراحی شد و با برنامه‌نویسی در محیط# C Visual پیاده‌سازی گردید. صحت این کار با مقایسه‌ی نتایج بدست آمده از برنامه‌نویسی با نتایج آزمایشگاهی بررسی و تائید گردید. در ادامه‌ی این تحقیق، برنامه‌نویسی طوری توسعه داده شد که بتوان از آن جهت بهینه‌سازی طراحی استفاده نمود. بدین‌صورت که با مشخص کردن ابعاد مقطع و میزان آرماتور موجود همراه با بار محوری و لنگر خمشی وارد بر ستون و همچنین معرفی مشخصات ورق‌های FRP در دسترس به همراه قیمت آنها، برنامه‌نویسی انجام شده می‌تواند مشخص کند که کدام نوع FRP در صورت استفاده، ضمن تامین ظرفیت خمشی و محوری مورد نیاز دارای حداقل قیمت نیز می‌باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Strengthening Optimization of RC Columns with Rectangular Section by FRP Wrapping

نویسندگان [English]

  • Kourosh Nadimi Shahraki 1
  • Mohammad Reisi 2
1 Islamic Azad University KhomeiniShahr Branch
2 Islamic Azad Univiersity, Khomeinishahr branch
چکیده [English]

Wrapping reinforced concrete (RC) column with FRP sheets improves compressive strength of concrete. Since stress-strain curve of concrete confined with FRP is different from stress[1]strain curve of normal concrete, equations presented by codes for design and analysis of normal (unstrengthened) RC column and based on stress-strain curve of normal concrete cannot be used for design and analysis of columns strengthen with FRP. In this research, first by using stress-strain curve of confined concrete presented by researchers and ACI code, an algorithm was designed to determine axial and flexural capacity of strengthened column and implemented in Visual C# environment. Verification of this work was investigated and confirmed by comparing it with experimental results. The programming was developed in a way that it could be used to optimize the design. Thus, by specifying required information including cross sectional dimensions, number and diameter of rebars, applied axial load and bending moment on column, FRP sheet properties and price, the performed programming can determine which type of FRP, if used, while providing the required flexural and axial capacity , has also the minimum price.

کلیدواژه‌ها [English]

  • Confined Concrete
  • FRP sheets
  • Stress-Strain curve
  • optimization
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