نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه عمران سازه ، دانشکده فنی و مهندسی، دانشگاه آزاد واحد تبریز

2 دانش آموخته کارشناسی ارشد عمران، سازه، واحد قشم، دانشگاه آزاد اسلامی، قشم، ایران

10.30478/jcsm.2019.152292.1091

چکیده

اتصالات تیر - ستون در قابهای بتن مسلح از جمله عناصر کلیدی در تعیین رفتار سازه در مقابل انواع بارها می­باشد. نقش این اتصالات در مقابل بارهای جانبی بخصوص رخدادهای قوی لرزه­ای بسیار مهم بوده و رفتار سازه­های بتن مسلح در زلزله های گذشته نشان می­دهد که اتصالات تاثیر قابل توجهی در میزان و شدت خرابی­های حاصله داشته­اند. از سوی دیگر تجارب بدست آمده در زلزله­های گذشته منجر به در نظر گرفتن تمهیدات جدید طراحی اتصال در آیین نامه­های فعلی شده است. علی رغم اهمیت اتصالات مفصلی و همچنین استفاده فراوان از آنها در سازه­های فولادی، به علت عدم وجود جزئیات مطمئن کاربرد آنها در سازه­های بتنی بسیار اندک است. در این مقاله رفتار اتصالات در قاب­های بتنی ساختمانی در دو حالت گیردار و مفصلی و برای درصدهای مختلف تسلیح مقطع تیر در محیط نرم افزار ABAQUS  مدلسازی شده و مورد مقایسه قرار گرفته است. نتایج این تحقیق نشان دهنده آن است که با افزایش درصد آرماتورهای طولی در مقطع تیر در حالت استفاده از اتصالات گیردار منجر به افزیش شکل پذیری اتصال گردیده است. با این حال با افزایش درصد آرماتور و ثابت ماندن ابعاد هندسی تیر در نهایت شکل پذیری به تدریج دچار کاهش شده است.همچنین با افزایش درصد آرماتور در مقطع تیر در حالت استفاده از اتصالات مفصلی منجر به افزیش ظرفیت نهایی اتصال به صورت پیوسته ولی بسیار تدریجی می‌گردد.
 

کلیدواژه‌ها

عنوان مقاله [English]

Evaluation of the Comparative Effect of Seismic Behavior of Hinge and Fixed Connections on RC Structures Based on the Change in Reinforcement Ratio

نویسندگان [English]

  • yousef zandi 1
  • Ruhedin Gasemi Sardareh 2

1 Assistant Professor, Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran.

2 MSc in Civil Engineering,Structural Engineering from Geshm Branch, Islamic Azad University, Geshm, Iran.

چکیده [English]

 
Beam-Column joints in reinforced concrete frames are one of the key elements in determining the structural behavior of a variety of loads. The role of these joints against lateral loads, especially strong seismic events, is very important and the behavior of reinforced concrete structures in past earthquakes indicates that Connections have had a significant impact on the extent and severity of the failures. On the other hand, the experience gained in past earthquakes has led to the consideration of new interconnection design schemes in the current regulations. Despite the importance of joint joints and their extensive use in steel structures, due to the lack of precise details on their use in concrete structures, they are very small. In this paper, the behavior of joints on concrete frames in two types of absorption and bonding and for various reinforced sections of reinforced beams is modeled and compared in ABAQUS software environment. The results of this study indicate that increasing the percentage of the armature at the cross section in the case of the use of clamping joints has led to an increase in connective ductility. However, by increasing the reinforcement of the reinforcement and maintaining the geometric dimensions of the beam, the ultimate degree of ductility is gradually reduced. Also, with the increase in the diameter of the reinforcement in the beam during the use of joint joints, it increases the final capacity of the connection continuously but very gradually it turns out.
 

کلیدواژه‌ها [English]

  • : joint joints
  • bonding connection
  • seismic behavior of joints
  • armed cross section percentage of reinforced beam

 

1. ACI Committee 318-05. Building Code Requirements for Reinforced Concrete and commentary (ACT 318-05). American Concrete Institute, Detroit, 2005.

2. Nzs 3101.Code of Practice for the Design of Concrete Structures, Parts 1 and 2. Standard Association of New Zealand, wellington, 1995.

3. Architectural Instiute of Japan. Standard for structural Calculation of Reinforcad Concrete Structures. Architectural Institute of Japan, Japan, 1994.

4. Euro code 8 (EC8). Design of structures for earthquake resistance- part I: general rules, seismic actions and rules for building. Doc CEN/Tc250/SC8/N335prEN 1998-1-1, 2003.

5. CEB. RC Frames under Earthquake Loading – State of the Art Report, Comet’s Euro – International du B’eton, Thomas Telford, London, 1996.

6. Giberson MF. Two nonlinear beams with definition of ductility. Journal of the Structural Division (ASCE) 1969; 95(ST2):137-157.

7. Alath S, Kunnath S. Modeling inelastic shear deformation in RC beam- column joints. Proceedings of the 10th Conference on Engineering Mechanics, University of Colorado at Boulder, Boulder, Co, 1995; 822-825.

8. Biddah A, Ghobarah A.Modeling of shear deformation and bond slip in reinforced concrete joints. Journal of Structural Engineering and Mechanics 1999; 7(4):413-432.

9. ACI352R. (2002). Recommendations for design of beam-column connections in monolithic reinforced concrete structures (reported by Joint ACI-ASCE committee 352). American concrete Institute. U.S.A.

10. Park, R. & Paulay, T. (1975).Reinforced concrete structures. John Wiley & Sons. New York.

11. Tsonos, A. G, Tegos. I. A. & Penelis, G. (1993). Seismic resistance of type-2 exterior beam-column joints reinforcement with inclined bars. ACI Structural Journal, Vol. 89, No. 1, pp. 3-12.

12.Wallance, J. W., Scott, W. McConnell, Piush Guta & Paul, A. Cote. (1998). Used of headed reinforcement in beam-column joints subjected to earthquake loads. ACI Structural Journal, Vol. 95, No. 5, pp. 590-606.

13. Murty, C. V. R., Rai, D. C., Bajpai, K. K. & Sudhir K. Jain. (2003). Effectiveness of reinforcement details in exterior reinforcement concrete beam-column joints for earthquake resistance. ACI Structural Journal, Vol. 100, No. 2, pp. 149-156.

14. Uma, S. R. & Sudhir. K. Jain. (2006). Seismic design of beam-column joints on RC moment resisting framesreview of codes. Structural Engineering and Mechanics, Vol. 23, No. 5, pp. 579-597.

15. Chutarat, N. & Aboutaha, R. S. (2003). Cyclic response of exterior reinforcement concrete beam-column joints reinforced with headed bars-experimental investigation, ACI Structural Journal, Vol. 100, No. 2, pp. 259-264.

16. Lee. H. J. & Yu, S. Y. (2009). Cyclic response of exterior beam-column joints with different anchorage methods. ACI Structural Journal, Vol. 106, No. 3, pp. 329-339.

17. Bindhu, K. P. & Jeya, K. P. (2010). Strength and behavior of exterior beam-column joints with diagonal cross bracing bars. Asian journal of civil Engineering (Building and Housing), Vol. 11, No. 3, pp. 397-410.

18. Sagbas, G. Vecchio, F. J. & Christopoulos, C. (2011). Computational modeling of the seismic performance of beam-column subassemblies. Journal of Earthquake Engineering, Vol. 15, No. 4, pp. 640-663.

19. Baglin, P. S. & Scott, R. H. (2000). Finite element modeling of reinforced concrete beam-column connection. ACI structural journal, Vol.97, No. 6, pp. 886-894

20. Hegger. J., Sherif. A. & Roeser. W. (2004). Nonlinear finite element analysis of reinforced concrete beamcolumn connections. ACI Structural Journal, Vol. 101, No. 5, pp. 604-614

21. Park. S. & Mosalam, K. M. (2012). Analytical model for predicting shear strength of unreinforced exterior beam-column joints. ACI Structural Journal, Vol. 109, No. 2, pp. 149-160.

22. Chun, S. C., Lee, S. H., Kang, T. H. K., Oh, B. & Wallace, J. W. (2007). Mechanical anchorage in exterior beam-column joints subjected to cyclic loading. ACI Structural Journal, Vol. 104, No. 1, pp. 102–113.

23. Hau TTC. Unified Theory of Reinforced Concrete. CRC Press Inc: Boca Raton, FL, 1993.

24. Youssef M, GhobarahA. Modeling of RC beam- column joints and structural walls. Journal of Earthquake Engineering 2001; 5(1):93-111.

25. Lowes LN, Altoona A. Modeling reinforced- concrete beam- column joints subjected to cyching loading. Journal of Structural Engineering (ASCE) 2003; 129(12): 1686-1697.

26. Vecchio, F.J. and Collins, M.P.(1986), The Modified Compression Field Theory for Reinforced Concrete Elements Subjected to Shear, Journal of American Concrete Institute, 83:2,219-231.

27. Pampanin S, Magenes G, Carr A. Modeling of shear hinge mechanism in poorly detailed RC beam- column joints. Fib Symposium on Concrete Structures in Seismic Regions, Athens, Greecem 6-8 May 2003; Paper 171.

28. Priestley, MJN, Displacement – based seismic assessment of reinforced concrete buildings, Journal of Earthquake Engineering,1(1), 1997, 157-192.

29. Hakuto, S., Park, R. and Tanaka, H. Seismic load tests on interior and exterior beam- column joints with substandard reinforcing details. ACL Structural Journal, V. 97, N. 1, 11-25.2000.

30. Bing, Li, Yiming, W., Tso- Chien P. Seismic Behaviour of Non-seismically Detailed Interior Beam-Wide Column Joints – Part I: Experimental Results and Observed Behaviour, ACI. Structural Journal, Vol.99.No.6, 791-802, 2002.

31. Calvi, G.M., Magenes, G., Pampanin. S. Experimental Test on a Three Storey R.C. Frame Designed for Gravity only, 12 th European Conference on Earthquake Engineering, London, paper n.727, 2002.

32. Pampanin, S., Calvi, G.M. and Moratti, Seismic Response of Reinforced Concrete Buildings Designed For Gravity Loads. Part I: Experimental Test on Beam- Column Subassemblies, submitted to ASCE Journal of Structural Engineering, 2003a.

33. Pampanin, S. Magenes, G, Calvi, G.M. Seismic Response of Reinforced Concrete Buildings Designed For Gravity Loads. Part II: Experimental Test on a Three Storey Frame, submitted to ASCE Journal of Structural Engineering, 2003b.

34. Park, Y. J.Reinhorn, A.M. & Kunnath, S.K. 1987. IDARC: Inelastic Damage Analysis of Reinforced Concrete Frame_Shear well Structures. Technical Report NCEER-87-0008, 1987, State University of New York at Buffalo.

35. Pampanin, S.,Calve, G.M. and Moratti,M.Seismic Behavior of R.C. Beam-Column Joines Designed for Gravity Loads, 12 th European Conference on Earthquake Engineering, London, Paper n. 726, 2002.

36. Shin M,LaFave JM. Modeling of cyclic joint shear deformation contributions in RC beam_ column connections.

37. Karayannis CG. Chalioris CE, Sideris KK. Effectiveness of RC beam – column connection repair using epoxy resin injections. Journal of Earthquake Engineering 1998, 2 (2): 217-240