تأثیر استفاده از بتن پرمقاومت در روابط طراحی مقاومت برش سوراخ‌کننده‌ی صفحات تخت بتن‌آرمه

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده عمران، پردیس دانشکده‌های فنی، دانشگاه تهران، تهران، ایران

2 دانشکده عمران، دانشگاه صنعتی امیرکبیر، تهران، ایران

چکیده

بتن پرمقاومت به علت خصوصیات بهبودیافته‌ی خود به طور گسترده‌ای در چند دهه‌ی اخیر مورد استفاده قرار گرفته است. از بتن پرمقاومت در صفحات تخت نیز استفاده می‌شود. صفحات تخت به علت عمق محدودشان مستعد شکست تحت برش سوراخ‌کننده هستند. اکثر آیین‌نامه‌های طراحی بتن، برپایه‌ی آزمایشات روی نمونه‌های ساخته‌شده با بتن معمولی تدوین شده‌اند. حال آن‌که بتن پرمقاومت در مقایسه با بتن معمولی مکانیزم‌های گسیختگی متفاوتی دارد. ازین‌رو ضروری است تا روابط آیین‌نامه‌ها درخصوص بتن پرمقاومت ارزیابی شوند. هدف این مقاله بررسی اثرات استفاده از بتن پرمقاومت در روابط طراحی و یافتن مناسب‌ترین رابطه برای تخمین مقاومت برش سوراخ‌کننده‌ی صفحات تخت با ستون داخلی می‌باشد. روابط طراحی مورداستفاده در این پژوهش شامل روابط آیین‌نامه‌های طراحی ACI 318، Eurocode2، BS 8110، DIN 1045 و شش رابطه‌ی پیشنهادی توسط محققین برای بتن پرمقاومت می‌باشند. برای بررسی صحت روابط طراحی، از 50 نتیجه‌ی آزمایشگاهی برگفته از ادبیات فنی روی نمونه‌های دال ساخته‌شده با بتن پرمقاومت استفاده شده است و بهترین رابطه برای تخمین ظرفیت برش سوراخ‌کننده پیشنهاد می‌شود.

کلیدواژه‌ها


عنوان مقاله [English]

The Effect of High-Strength Concrete on Punching Shear Strength of Reinforced Concrete Flat Plates

نویسندگان [English]

  • Morvarid Hajian 1
  • Seyed Alireza Fatemi 2
  • Iraj Mahmoudzadeh Kani 1
1 School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran
2 Department Of Civil Engineering, Amirkabir University of Technology, Tehran, Iran
چکیده [English]

High strength concrete (HSC) has been used widely over the last decade due to its improved characteristics. HSC has also been widely used in flat plates. Flat plates due to their limited depth are sensitive to punching shear. Most of the current design codes are based on empirical researches conducted on normal strength concrete (NSC) specimens. HSC has different fracture mechanisms compared to NSC. Therefore, it is essential to re-examine codes equations in order to be proper for HSC members. The aim of this paper is to investigate the effect of using HSC on current design relationships and find the most convenient formula for predicting the punching shear capacity of interior slab-column connections. Design formulas used in this research consist of four design codes, ACI 318, Eurocede2, BS 8110, DIN 1045 and six proposed formulas by other researchers for HSC flat plates. For checking the accuracy of these design methods, 50 test results from the literature conducted on HSC slab specimens are elected to compare with formulas.

کلیدواژه‌ها [English]

  • high strength concrete
  • punching shear strength
  • flat plates
  • interior slab-column connections
 
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