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

 

[1] Elsanadedy, H.M., Al-Salloum, Y.A. and Alsayed, S.H. (2013). “Prediction of punching shear strength of HSC interior slab-column connections”, KSCE J. Civ. Eng., 17(2): 473-485.

[2] Ngo, D.T. (2001). “Punching shear resistance of high-strength concrete slabs”, Electron. J. Struct. Eng., 1(1):  52-59.

[3] Inácio, M.M., Almeida, A.F., Faria, D.M., Lúcio, V.J. and Ramos, A.P. (2015). “Punching of high strength concrete flat slabs without shear reinforcement”, Eng. Struct., 103: 275-284.

[4] Theodorakopoulos, D.D. and Swamy, R.N. (2002). “Ultimate punching shear strength analysis of slab–column connections”, Cem. Concr. Compos., 24(6): 509-521.

[5] Ramana, N.V., Gnaneswar, K., Sashidhar, C. and Kumar, T.N. (2012). “Behavior of High Performance Concrete Two Way Slabs in Punching Shear”, Int. j. sci. adv. technol., 2(3): 122-126.

[6] Wight, J.K, and MacGregor, J.G. (2012). Reinforced Concrete Mechanics and Design, 6th Edition, Pearson Education, Inc., Upper Saddle River, New Jersey.

[7] Ghannoum, C.M. (1998). Effect of High-strength Concrete on the Performance of Slab-column Specimens. MSc. Thesis, McGill University Montréal, Canada.

[8] Ramdane, K. E. (1996). “Punching shear of high performance concrete slabs”, 4th Int. Symposium on Utilization of High-strength/High-Performance Concrete, Paris, pp.: 1015-1026.

[9] Subramanian, N. (2005). “Evaluation and enhancing the punching shear resistance of flat slabs using HSC”, Indian Concr. J., 79(4): 31-37.

[10] Marzouk, H. and Hussein, A. (1992). “Experimental investigation on the behavior of high-strength concrete slabs”, ACI Struct. J., 88(6): 701-713.

[11] Gardner, N.J. (1990). Relationship of the punching shear capacity of reinforced concrete slab with concrete strength”, ACI Struct. J., 87(1): 66-71.

[12] Nawy, E.G. (2001). Fundamentals of High-Performance Concrete, 2th Edition, John Wiley and Sons, Inc., Toronto, Canada.

[13] Regan, P.E., Al-Hussaini, A., Ramdane, K.E. and Xue, H.Y. (1993). “Behaviour of high strength concrete slabs”, In Concrete 2000. Proceedings of International Conference, University of Dundee, Scotland, UK, September, 1: 761-773.

[14] ACI Committee 318. (2014). “Building Code Requirements for Structural Concrete and Commentary, ACI 318-14 and 318R-14”, American Concrete Institute, Farmington Hills, Michigan.

[15] British Standard. (1997). “Structural Use of Concrete, Part 1: Code of Practice for Design and Construction, BS 8110”, British Standards Institution, London,  UK

[16] Eurocode 2. (2004). “Eurocode 2: Design of Concrete Structures- part 1-1: General Rules and Rules for Buildings”, European Committee for Standardization.

[17] DIN 1045. (2001). “German Standard: Concrete Reinforced and Prestressed Concrete Structures Part 1: Design”, Deutsche Institut fur Normung e.v., Beuth Verl, Berlin.

[18] Subramanian, N. (2003). “Shear strength of high strength concrete beams: Review of codas provisions”, Indian Concr. J., 77(5): 1090-1094.

[19] Hallgren, M. and Kinnunen, S. (1996). “Increase of punching shear capacity by using high-strength concrete”, In 4th International. Symposium on Utilization of High-strength/High-performance Concrete, Paris, pp.: 1037-1046.

[20] Hallgren M. (1996). Punching shear capacity of reinforced high strength concrete slabs, Bulletin No 23. Department of Structural Engineering, KTH, Stockholm.

[21] Tomaszewicz, A. (1993). High-strength concrete SP2-plates and shells. Report 2.3, Punching Shear Capacity of Reinforced Concrete Slabs, Report No. STF70A93082, SINTEF, Trondheim.

[22] Marzouk, H., Emam, M. and Hilal, M.S. (1998). “Effect of high-strength concrete slab on the behavior of slab-column connections”, ACI Struct. J., 95(3): 227-237.

[23] Marzouk, H. and Jiang, D. (1997). “Experimental investigation on shear enhancement types for high-strength concrete plates”, ACI Struct. J., 94(1): 49-58.

[24] Rankin, G.I.B. and Long, A.E. (1987). “Predicting the punching strength of conventional slab-column specimens”, Proc. Inst. Civ. Eng. (London), 82(2): 327-346.

[25] Sherif, A.G. and Dilger, W.H. (1996). “Critical review of the CSA A23.3-94 punching shear strength provisions for interior columns”, Can. J. Civil. Eng., 23(5): 998-1011.

[26] Gardner, N.J. and Shao, X. (1996). “Punching shear of continuous flat reinforced concrete slabs”, ACI Struct. J., 93(2): 218-228.

[27] El-Gamal, S. and Benmokrane, B. (2004). A new punching shear equation for two way concrete slabs reinforced with FRP bars, Research Study, American Concrete Institute, Advancing Concrete Knowledge, SP-230-50.