بررسی عددی رفتار ستون های بتنی مسلح شده با فولاد با هسته صلیبی تحت بار با خروج از مرکزیت

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار، دانشکده مهارت و کارآفرینی، واحد بابل، دانشگاه آزاد اسلامی، بابل، ایران

2 دانشیار، گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه مازندران، بابلسر، ایران

چکیده

ستون های بتنی مسلح شده با فولاد SRC به دلیل مزایای فراوانی که دارند، استفاده از آنها در سال های اخیر رواج زیادی پیدا کرده است. در این تحقیق، به جهت بررسی رفتار ستون های SRC با هسته فولادی صلیبی، شاخص شکل پذیری و عوامل موثر بر آن مورد بررسی قرار گرفته و همچنین با محاسبه روابط لازم بر اساس روش توزیع تنش پلاستیک، روشی ساده و کاربردی برای طراحی این ستون ها ارائه گردید. بر همین اساس، یک مدل المان محدود به کمک نرم افزار آباکوس به جهت مطالعه عددی ایجاد شد که با نتایج مدل آزمایشگاهی اعتبارسنجی گردید. در مجموع 16 ستون با هسته فولادی صلیبی برای مطالعه عددی تحلیل گردیدند که متغیرهایی از قبیل درصد هسته فولادی، مقاومت فشاری بتن، نسبت فاصله میلگردهای عرضی، نسبت لاغری و نسبت برون محوری نیرو بر شاخص شکل پذیری این ستون‌ها مورد بحث و ارزیابی قرار گرفتند. نتایج نشان دهنده این مطلب بوده که با افزایش نسبت برون محوری، ظرفیت باربری کاهش ولی شاخص شکل‌پذیری به دلیل تغییر رفتار از حالت فشاری به خمشی افزایش می یابد به طوری که با افزایش نسبت برون محوری از 1/0 به 4/0 ظرفیت باربری به مقدار 1/59% کاهش یافته ولی شاخص شکل پذیری 2/28% افزایش می یابد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical Investigation of Behavior of Steel-Reinforced Concrete Columns with Cruciform Steel Core under Eccentric Loading

نویسندگان [English]

  • Mohsen Ahmadi 1
  • Mahdi Nematzadeh 2
1 Assistant Professor, College of Skills and Entrepreneurship, Babol Branch, Islamic Azad University, Babol, Iran
2 Associate Professor, Department of Civil Engineering, Faculty of Engineering and Technology, University of Mazandaran, Babolsar, Iran
چکیده [English]

Steel reinforced concrete (SRC) columns have become very popular in recent years due to their many advantages. In this study, to investigate the behavior of SRC columns with a cruciform steel section at their core, the ductility index and factors affecting it were investigated. Also, by calculating the necessary equations based on the plastic stress distribution method, a simple and practical method for designing these columns was provided. Accordingly, a finite element model was created using ABAQUS software for numerical study and was then validated with the results of a previous experimental study. A total of 16 columns with cruciform steel cores were analyzed for the present study. The effect of variables such as steel core percentage, concrete compressive strength, stirrup spacing, slenderness ratio, and load eccentricity ratio on the ductility index of these columns was discussed. The results showed that with increasing the eccentricity ratio, the bearing capacity decreases but the ductility index increases due to the change in behavior from compressive to flexural, such that as the eccentricity ratio increased from 0.1 to 0.4, the bearing capacity decreased by 59.1% but the ductility index increased by 28.2%.

کلیدواژه‌ها [English]

  • Composite Column
  • SRC
  • Concrete confinement
  • Load-bearing capacity
  • Eccentric loading
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  • تاریخ دریافت: 20 آبان 1400
  • تاریخ بازنگری: 12 بهمن 1400
  • تاریخ پذیرش: 16 بهمن 1400
  • تاریخ اولین انتشار: 16 بهمن 1400