İnceltilmiş Uçlu Önüretimli Aşık Kirişlerinin Yük Taşıma Kapasitelerinin Deneysel ve Numerik Olarak İrdelenmesi ve Çözüm Önerileri

Öz

Türkiye’de inşaat sektörü 1960’lı yılların sonu itibari ile beton prefabrikasyon ile tanışmıştır. Prefabrike olarak üretilen yapılar seri üretimlerinin ve montajlarının hızlı olmasından dolayı özellikle sanayi yapılarında daha fazla tercih edilmişlerdir. Bu yapı türünün en büyük dezavantajı özellikle mafsallı birleşim bölgelerinde oluşan hasarlardır. Çatı kirişleri ile aşık kirişlerinin birleştiği bölgelerde de bağlantı genellikle mafsallı olarak gerçekleştirilir. Bundan dolayı mesnet bölgelerinde teorik olarak moment oluşmamakta ve bu tip kirişlerin kesit tesirleri basit mesnetli kirişlerde olduğu gibi hesaplanmaktadır. Ancak aşık inceltilmiş uç bölgelerinde yoğunlaşan kesme kuvveti, kesme gerilmelerinin artmasına neden olduğundan bu bölgenin detaylandırılması için bir takım özel tasarım kuralları ilgili standartlarda yer almıştır. Bu birleşim bölgelerinde özellikle etkili ve uzun süreli kar yağışlarından sonra çatıda biriken yoğun kar neticesinde hasarlar gözlemlenmektedir. Bu hasarlar nispeten daha eski prefabrike yapı stokunda bulunanlar başta olmak üzere inceltilmiş uçlu aşık kirişleri için önemli bir risk oluşturmaktadır. Bu çalışmada, şimdiye kadar kapsamlı olarak araştırılmamış olan inceltilmiş uçlu aşıkların düşey yük etkisi altında davranışları, aşıkların değişen mekanik parametrelerine göre deneysel ve numerik olarak incelenmiştir. İlk olarak yürürlükteki standartlara uygun olan ve olmayan iki adet aşık kirişinin deneyleri gerçekleştirilmiştir. Ardından yine standarda uygun bir adet aşık kiriş inceltilmiş uç hasarının önlenlenmesi amacıyla CFRP ile güçlendirilerek test edilmiştir. Daha sonra ABAQUS programıyla modellenen aşıklardan elde edilen sonuçlar ile deneysel çalışma sonuçları ile doğrulanmıştır. Tüm deneysel sonuçlarla numerik modelleme sonuçlarının oldukça yakın olduğu görülmüştür. Numerik model numunelerinde gözlenen hasarlar ile deneylerde oluşan hasarların benzer olması yeni parametrik çalışmalarda numerik modellerin kullanılabileceğini göstermiştir. Doğrulamanın ardından aşıkların mekanik özellikleri ile güçlendirme alternatiflerine bağlı bir dizi parametrik çalışma numerik olarak gerçekleştirilmiştir. Parametrik çalışmada; özellikle mevcut aşıklarda beton basınç dayanımı, donatı çekme dayanımı ve aşık kirişlerin üretiminde kullanılan öngerme seviyesinin tasarlanandan farklı olabileceği düşüncesiyle bir parametre olarak değerlendirilmiştir. Ayrıca karbon elyaf takviyeli polimer (CFRP) kumaş ile güçlendirilen ve yönetmeliğe göre tasarlanmayan aşıkların davranışı da yine parametrik çalışma kısmında incelenmiştir. Parametrik çalışmanın sonuçlarına göre beton basınç dayanımı daha etkin olmakla beraber beton ve çelik dayanımının artışı ile kesme kapasitesinde önemli ölçüde artış sağlandığı görülmüştür. Elde edilen sonuçlarda öngerme değeri artışının kapasiteye hatırı sayılır bir etki sağlamadığı görülmüştür. CFRP ile güçlendirilen numunelerde aşığın yük taşıma kapasitesinin %50’ye arttığı ve hasarın inceltilmiş uç bölgesi dışına kaydığı (inceltilmemiş bölgeye) görülmüştür. Parametrik çalışma ile farklı ve uygulanabilir CFRP alternatifleri de modellenerek en iyi güçlendirme alternatifi önerildi. Bununla beraber inceltilmiş uçlu aşıkların donatı tasarımına esas bazı öneriler getirilmiştir.

Anahtar Kelimeler

• ABAQUS
• CFRP malzeme
• İnceltilmiş uç
• aşık kiriş
• prefabrik yapı

Experimental and Numerical Investigation of Load Bearing Capacity of Thinned End Precast Purlin Beams and Solution Proposals

Öz

The construction sector in Turkey has met concrete prefabrication at the end of the 1960s. Prefabricated structures have been preferred more especially in industrial buildings due to their rapid production and fast erecting. The biggest disadvantage of these structures is the damages that occurred at especially the region of hinged connection. The connection of roof beams and purlin beams are generally assembled with a hinged connection. Therefore, a moment does not occur theoretically in the support areas and the cross-sectional effects of these beams are calculated as in simple support beams. However, since the shear force concentrated in the thinned end regions causes an increase in shear stresses, a number of special design rules are included in the relevant standards for the detailing of this region. Damages are observed in these connections as a result of snow accumulated on the roof especially after effective and prolonged snowfall. These damages pose a significant risk for thinned end beams, especially those in the relatively older prefabricated building stock. In this present study, the behavior of thinned end purlins under vertical loading, which have not been investigated extensively before, has been numerically and experimentally examined according to varying mechanical parameters. First, experiments of two purlin beam, which are in accordance with current standards and not, were carried out. Then another purlin beam in accordance with the standard, which was strengthened with carbon fiber reinforced polymer (CFRP) in order to prevent thinned end damage, was tested. Then, the results obtained from the purlins modeled with ABAQUS program were verified with the results of the experimental study. The results of numerical modeling were found to be very close to all experimental findings. The similarities between the damages observed in the experiments and numerical modeling showed that numerical models can be used in new parametric studies. After the verificifation, a number of parametric studies related to the mechanical properties of the purlins and strengthening alternatives were performed numerically. In the parametric study, concrete compressive strength, reinforcement tensile strength and the pre-stressing level used in the production of purlin beams, especially in existing purlin, was evaluated as a parameter with the idea that it may differ from the designed one. In addition, the behavior of purlins which are not in accordance with standards and strengthened with CFRP was also examined in the parametric study section. According to the results of the parametric study, it has been observed that a significant increase in shear capacity has been achieved with the increase of concrete and steel strength although the concrete compressive strength is more effective. The results showed that increasing the pretension value does not have a significant effect on the capacity. In addition, the shear capacity of purlin strengthened with CFRP has increased up to 50% and the damage has shifted to out of the thinned end region. With the aid of parametric study, different and feasible CFRP alternatives were also modeled and the best strengthening alternative was recommended. In addition, some suggestions for the design of the reinforcements for the thinned ended purlins were made.

Anahtar Kelimeler

• ABAQUS
• CFRP
• thinned end
• purlin
• prefabricated building

Kaynakça

1. [1] Günerman, H., Prefabrike Bina Sistemleri. Prefabrike İnşaat Teknolojileri Sempozyumu, 23-6, 1997.
2. [2] Şenel, Ş.M., Palanci, M., Kalkan, A., Yılmaz, Y., Mevcut Prefabrik Binaların Mafsallı Birleşimlerinin Kesme ve Devrilme Güvenliğinin Araştırılması, Teknik Dergi, 24, 119, 2013.
3. [3] Taştekin, M.S., Sanayi yapılarında prefabrik betonarme ve çelik konstrüksiyon uygulamalarının ekonomik yönden karşılaştırılması, Yüksek Lisans Tezi, Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2006.
4. [4] Reynolds, G., The strength of half-joints in reinforced concrete beams, Cement and Concrete Association, 1969.
5. [5] Mattock, A.H., Chan, T.C., Design and behavior of dapped-end beams, PCI journal, 24, 28-45, 1979.
6. [6] Mattock, A., Theryo, T., Strength of Prestressed concrete members with dapped ends-reply, Journal Prestressed Concrete Institute, 32, 120-1, 1987.
7. [7] Solanki, H., Strength of Prestressed Concrete Members with Dapped Ends-Comment, Journal Prestressed Concrete Instute, 32, 119-20, 1987.
8. [8] Shakir, Q.M., Reinforced Concrete Dapped End Beams–State of the Art, International Journal of Applied Science, 1, 2, 44-57, 2018.

9. [9] Ahmad, S., Elahi, A., Junaid, H.M.F., Ahsan, Z., Evaluation of the shear strength of dapped ended beam, Life Science Journal, 10, 1038-44, 2013.
10. [10] Yazman, Ş., Aksoylu, C., Özkılıç, Y., Gemi, L., Arslan, M.H., Sanayi Yapılarında Kullanılan Betonarme Prefabrike Öngerilmeli Aşıkların Kesme ve Eğilme Kapasitelerini Artırmaya Yönelik CFRP Uygulaması, International Science and Academic Congress (INSAC'19), 292-8, 2019.
11. [11] Aksoylu, C., Yazman, Ş., Özkılıç, Y., Gemi, L., Arslan, M.H., İnceltilmiş Uçlu Betonarme Prefabrik Aşıkların Kesme Kapasitelerinin CFRP uygulaması ile Artırılması. International Science and Academic Congress(INSAC'19), 285-91, 2019.
12. [12] Özkılıç, Y., Aksoylu, C., Yazman, Ş., Gemi, L., Arslan, M.H., Prefabrike İnceltilmiş Aşık Uçlarının Deneysel ve Numerik Sonlu Eleman Analizlerinin Karşılaştırılması. International Science and Academic Congress(INSAC'19), 299-307, 2019.
13. [13] Hwang, S-J., Lee, H-J., Strength prediction for discontinuity regions by softened strut-and-tie model, Journal of Structural Engineering, 128, 1519-26, 2002.
14. [14] Aksoylu, C., Özkılıç, Y.O., Yazman, Ş., Gemi, L., Arslan, M.H., The Numerical Study of The Effects of Steel Reinforcement Ratio to Behavior of Prefabricated Purlins, 2nd International Congress on Engineering and Architecture (ENAR), 1759-65, 2019.
15. [15] Aswin, M., Mohammed, B.S., Liew, M., Imam, Z.S., Root cause of reinforced concrete dapped-end beams failure, Abu Dhabi University, 2015.
16. [16] Aswin, M, Mohammed BS, Liew M, Syed ZI. Shear failure of RC dapped-end beams. Advances in Materials science and engineering, 11, 2015.
17. [17] Aswin, M., Syed, Z.I., Wee, T., Liew, M.S., Prediction of failure loads of RC dapped-end beams, Applied Mechanics and Materials, Trans Tech Publ, 567, 463-8, 2014.
18. [18] Atta, A., Taman, M., Innovative method for strengthening dapped-end beams using an external prestressing technique, Materials and Structures, 49, 3005-19, 2016.
19. [19] Hussain, H.N., Shakir, Q.M., Experimental Study of the Behavior of Reinforced Concrete Beams with Composite Dapped End under Effect of Static and Repeated Loads, International Journal of Applied Science, 2, 43-55, 2019.
20. [20] Kotsovos, G.M., Cotsovos, D.M., Half-joint beam design based on the CFP theory, Proceedings of the Institution of Civil Engineers-Structures and Buildings, 768-777, 2019.
21. [21] Lin, I-J., Hwang, S-J., Lu, W-Y., Tsai, J-T., Shear strength of reinforced concrete dapped-end beams, Structural Engineering and Mechanics, 16, 275-94, 2003.
22. [22] Lu, W.Y., Lin, I.J., Hwang, S.J., Lin, Y.H., Shear strength of high‐strength concrete dapped‐end beams, Journal of the Chinese Institute of Engineers, 26, 671-80, 2003.
23. [23] Lu, W-Y., Lin, I-J., Yu, H-W., Behaviour of reinforced concrete dapped-end beams, Magazine of Concrete Research, 64, 793-805, 2012.
24. [24] Mata-Falcón, J., Pallarés, L., Miguel, P.F., Proposal and experimental validation of simplified strut-and-tie models on dapped-end beams, Engineering Structures, 183, 594-609, 2019.
25. [25] Moreno-Martínez, J.Y., Meli, R., Experimental study on the structural behavior of concrete dapped-end beams, Engineering Structures, 75, 152-63, 2014.
26. [26] Nagrodzka-Godycka, K., Piotrkowski, P., Experimental Study of Dapped-End Beams Subjected to Inclined Load, ACI Structural Journal, 109, 11-20, 2012.
27. [27] Peng, T., Influence of detailing on response of dapped-end beams [Ms Thesis], McGill University Montréal, Canada, 2009.
28. [28] Rymeš, J., Štemberk, P., Kohoutkova, A., Experimental Analysis of Strengthening of Dapped-End Beams, Key Engineering Materials: Trans Tech Publ, 241-6, 2017.
29. [29] Shakir, Q.M., Alliwe, R., Behavior of Self-Compacting Reinforced Concrete Dapped End Beams, International Journal of Applied Science, 2, 43-55 , 2019.
30. [30] Syed, Z.I., Sami, E., Ahmed, M.O., Modelling of Dapped-End Beams under Dynamic Loading, Abu Dhabi University, 2017.
31. [31] Özkılıç, Y., Aksoylu, C., Yazman, Ş., Gemi, L., Arslan M.H., The Effects of Material Properties and Pretension to Behavior ofPrefabricated Purlins, 2nd International Congress on Engineering and Architecture (ENAR), 1754-8, 2019.
32. [32] Yazman, Ş., Aksoylu, C., Özkılıç, Y.O., Gemi, L., Arslan, M.H., Experimental and Numerical Investigation of Prefabricated Thinned Ended Purlins with and without CFRP Composites, 2nd International Congress on Engineering and Architecture (ENAR), 575-9, 2019.
33. [33] Yang, K-H., Ashour, A.F., Lee, J-K., Shear strength of reinforced concrete dapped-end beams using mechanism analysis, Magazine of Concrete Research, 63, 81-97, 2011.
34. [34] Aksoylu C, Özkılıç YO, Arslan MH. Damages on Prefabricated Concrete Dapped-End Purlins due to Snow Loads and a Novel Reinforcement Detail. Engineering Structures. 2020 (Baskıda) .
35. [35] Handbook PD., Precast and prestressed concrete. Precast/Prestressed Concrete Institute, Chicago, IL, 1999.
36. [36] TS9967., Yapı Elemanları, Taşıyıcı Sistemler ve Binalar-Prefabrike Betonarme ve Öngerilmeli Betondan-Hesap Esasları ile İmalat ve Montaj Kuralları, Türk Standartları Enstitüsü, İstanbul, 1992.
37. [37] TS3233., Öngerilmeli Yapıların Hesap ve Yapım Kuralları, Türk Standartları Enstitüsü. 1-44, 1979.
38. [38] Barka, G., Ataköy, H., Yüksel, E., Beton Prefabrikasyon El Kitabı, Tasarım, Üretim ve Montaj Esasları, Türkiye Prefabrik Birliği, 2018.
39. [39] TBDY2019., Türkiye Bina Deprem Yönetmeliği, Deprem Etkisi Altında Binaların Tasarımı İçin Esaslar, Ankara.
40. [40] Standard T., Eurocode 1-Actions on structures-Part 1-3, General actions-Snow loads (TS EN 1991-1-3), Institute of Turkish Standard (TSE), Ankara, Turkey. 2007.
41. [41] Chen, B.S., Hagenberger ,M.J., Breen, J.E., Evaluation of strut-and-tie modeling applied to dapped beam with opening, Structural Journal, 99, 445-50, 2002.
42. [42] Committee, A., Standardization IOf. Building code requirements for structural concrete (ACI 318-08) and commentary, American Concrete Institute, 2008.
43. [43] Gundogan, G., İnceltilmiş Uçlu Prefabrike Kiriş Birleşimlerinin Türk (TS9967) ve Amerikan (PCI) Yönetmelikleriyle Karşılaştırılması [Yüksek Lisans], Eskişehir Osmangazi Üniversitesi, Fen Bilimleri Enstiüsü, 2010.
44. [44] Enstitüsü TS., TS 500 Betonarme Yapıların Tasarım ve Yapım Kuralları, Ankara, Türkiye, 2000.
45. [45] Aksoylu, C., Kara, N., Strengthening of RC frames by using high strength diagonal precast panels, Journal of Building Engineering., 31, 101338, 2020.
46. [46] Aksoylu, C., Sezer, R., Investigation of precast new diagonal concrete panels in strengthened the infilled reinforced concrete frames, KSCE Journal of Civil Engineering, 22, 236-46, 2018.
47. [47] Aksoylu, C., Kara, N., Güçlendirme Tekniği Olarak Yeni Nesil Ön Üretimli Beton Panel Uygulamasının Araştırılması, Selçuk Üniversitesi Mühendislik, Bilim ve Teknoloji Dergisi, 7, 346-61, 2019.
48. [48] Madenci, E., Özkılıç, Y.O., Gemi, L., Experimental and theoretical investigation on flexure performance of pultruded GFRP composite beams with damage analyses, Composite Structures, 242, 112162, 2020.
49. [49] Özkılıç, Y.O., Madenci, E., Gemi, L., Tensile and Compressive Behaviors of the Pultruded GFRP Lamina, Turkish Journal of Engineering (TUJE), 4, 169-75, 2020.
50. [50] Ghatte, H.F., Comert, M., Demir, C., Akbaba, M., Ilki, A., Seismic Retrofit of Full-Scale Substandard Extended Rectangular RC Columns through CFRP Jacketing, Test Results and Design Recommendations, Journal of Composites for Construction, 23, 04018071, 2019.
51. [51] Cosgun, C., Cömert, M., Demir, C., İlki, A., Seismic Retrofit of Joints of a Full-Scale 3D Reinforced Concrete Frame with FRP Composites, Journal of Composites for Construction, 23, 04019004, 2019.
52. [52] Ates, A.O., Khoshkholghi, S., Tore, E., Marasli, M., Ilki, A., Sprayed Glass Fiber–Reinforced Mortar with or without Basalt Textile Reinforcement for Jacketing of Low-Strength Concrete Prisms, Journal of Composites for Construction, 23, 04019003, 2019.
53. [53] Köroğlu, M.A., Ceylan, M., Arslan, M.H., İlki, A., Estimation of flexural capacity of quadrilateral FRP-confined RC columns using combined artificial neural network, Engineering Structures, 42, 23-32, 2012.
54. [54] Ilki, A., Bedirhanoglu, I., Kumbasar, N., Behavior of FRP-Retrofitted Joints Built with Plain Bars and Low-Strength Concrete, Journal of Composites for Construction, 15, 312-26, 2011.
55. [55] Ilki, A., Demir, C., Bedirhanoglu, I., Kumbasar, N., Seismic Retrofit of Brittle and Low Strength RC Columns Using Fiber Reinforced Polymer and Cementitious Composites, Advances in Structural Engineering, 12, 325-47, 2009.
56. [56] Arslan, M.H., Aksoylu, C., Gemi, L., Yazman, Ş., Özkılıç, Y.O., Effect of Circular Holes in Shear Region on the Behavior of CFRP Strengthened RC Beams, 4th Eurasian Conference on Civil and Environmental Engineering (ECOCEE), İstanbul, 860-5, 2019.
57. [57] Çetinkaya, N., Kaplan, H., Şenel, Ş.M., Betonarme Kirişlerin Lifli Polimer (FRP) Malzemeler Kullanılarak Onarım ve Güçlendirilmesi, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 10, 291-8, 2011.
58. [58] Ertürkmen, D., Dündar, C., Tokgöz, S., Karbon lifli polimer sargılı standart silindir beton numunelerin eksenel yük altındaki davranışlarının incelenmesi, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 23, 679-86, 2017.
59. [59] Gemi, L., Köroğlu, M.A., Çekme Bölgesi Lifli Beton Olan Cam Fiber Takviyeli Polimer (GFRP) ve Çelik Donatılı Etriyesiz Kirişlerin Eğilme Etkisi Altındaki Davranışı ve Hasar Analizi, S.Ü Müh Bilim ve Tekn Derg., 6, 654-67, 2018.
60. [60] Gemi, L., Köroğlu, M.A., Ashour, A., Experimental study on compressive behavior and failure analysis of composite concrete confined by glass/epoxy±55 filament wound pipes, Composite Structures, 187, 157-68, 2018.
61. [61] Gemi, L., Madenci, E., Özkılıç, Y.O., An Investigation on Effect of Steel/Glass Fiber Bars in Concrete Beams, VI International Earthquake Symposium (IESKO 2019), 651–6, 2019.
62. [62] Gemi. L., Özkılıç, Y.O., Madenci, E., Investigation of Flexural Behavior of FRP Wrapped and Concrete Filled GFRP Box Profile Beams, VI International Earthquake Symposium (IESKO 2019), 605–10, 2019.
63. [63] Kang, T.H-K., Ary, M.I., Shear-strengthening of reinforced & prestressed concrete beams using FRP: Part II—Experimental investigation. International Journal of Concrete Structures and Materials, 6, 49-57, 2012.
64. [64] Kuntal, V.S., Chellapandian, M., Prakash, S.S., Efficient near surface mounted CFRP shear strengthening of high strength prestressed concrete beams–An experimental study, Composite Structures, 180, 16-28, 2017.
65. [65] Özcan Z, Yöntem K. Betonarme Kirişlerin Kompozit Malzemeler ile Güçlendirilmesi, Deprem Sempozyumu, 1016-1022, 2005.
66. [66] Özkılıç, Y.O., Madenci, E., Gemi, L., Performance of Pultruded Glass Fiber Reinforced Polymer Composite Beams under Quasistatic Load, In The 5th International Conference on Engineering Science (ICES-2019), 2019.
67. [67] Pohl, G., Textiles., Polymers and composites for buildings, Elsevier, 2010.
68. [68] Sayın, B., Manisalı, E., Lif Takviyeli Plastik Levhalar ile Güçlendirilmiş Betonarme Kirişlerde Arayüz Gerilmelerini Etkileyen Parametreler, Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi, 16, 63-75, 2010.
69. [69] Soyaslan, A.E., Demiray, D., Tekstil Malzemelerinin İnşaat Mühendisliği Uygulamaları, Mehmet Akif Ersoy Üniversitesi Fen Bilimleri Enstitüsü Dergisi, 7, 29-34, 2016.
70. [70] Aytaç, E., CFRP güçlendirme malzemesi ve güçlendirme teknikleri [Yüksek Lisans Tezi], Dokuz Eylül Üniversitesi, 2011.
71. [71] Gemi, L., Investigation of the effect of stacking sequence on low velocity impact response and damage formation in hybrid composite pipes under internal pressure, A comparative study, Composites Part B, Engineering, 153, 217-32, 2018.
72. [72] Morkavuk, S., Köklü, U., Bağcı, M., Gemi, L., Cryogenic machining of carbon fiber reinforced plastic (CFRP) composites and the effects of cryogenic treatment on tensile properties, A comparative study. Composites Part B, Engineering, 147, 1-11, 2018.
73. [73] Özütok, A., Madenci, E., Static analysis of laminated composite beams based on higher-order shear deformation theory by using mixed-type finite element method, International Journal of Mechanical Sciences, 130, 234-43, 2017.
74. [74] Mohandoss P., Pilla R.G., Sengupta A.K., "Effect of compressive strength of concrete on transmission length of pre-tensioned concrete systems" 23, 304-313, Structures, 2020.
75. [75] Alberto T.Ramirez-Garciaa, Royce W.Floydb, W.Micah Halea, J.R.Martí-Vargasc, Effect of concrete compressive strength on transfer length, 5, 131-140, Structures,2016.
76. [76] R.W. Barnes J.W. GroveN.H. Burns, “Experimental Assessment of Factors Affecting Transfer Length” 100(6):740-748, ACI Structural Journal, 2003.
77. [77] Jin Kook Kim, Jun-Mo Yang, Hong Jae Yim, “Experimental Evaluation of Transfer Length in Pretensioned Concrete Beams Using 2,400-MPa Prestressed Strands”, Journal of Structural Engineering 142(11):04016088, 2016.
78. [78] Ahmed Ghallab, A.W. Beeby, “Factors affecting the external prestressing stress in externally strengthened prestressed concrete beams”, Cement and Concrete Composites 27(9-10):945-957,2005.
79. [79] Gemi, L., Aksoylu, C., Yazman, Ş., Özkılıç, Y.O., Arslan MH. Experimental investigation of shear capacity and damage analysis of thinned end prefabricated concrete purlins strengthened by CFRP composite, Composite Structures, 229, 111399, 2019.
80. [80] Eurocode2., Design of Concrete Structures-Part 1-1, General Rules and Rules for Buildings, 2005.
81. [81] du Béton FI., Practitioners guide to finite element modelling of reinforced concrete structures, State-of-Art Report, 2008.
82. [82] Desnerck, P., Lees, J.M., Morley, C.T., Strut-and-tie models for deteriorated reinforced concrete half-joints, Engineering Structures, 161, 41-54, 2018.
83. [83] Fernández, R.M., Muttoni, A., On development of suitable stress fields for structural concrete, ACI, Structural Journal, 104, 495-502, 2007.
84. [84] Mitchell, D., Cook, W.D., Peng, T., Importance of reinforcement detailing. Special Publication, 273, 1-16, 2010.
85. [85] Schlaich, J., Schäfer, K., Jennewein, M., Toward a consistent design of structural concrete, PCI journal, 32, 74-150, 1987.
86. [86] Tjhin, T.N., Kuchma, D.A., Computer-based tools for design by strut-and-tie method: Advances and challenges, Structural Journal, 99, 586-94, 2002.
87. [87] Wang, Q., Guo, Z., Hoogenboom, P.C., Experimental investigation on the shear capacity of RC dapped end beams and design recommendations, Structural Engineering and Mechanics, 21, 221, 2005.
88. [88] Bergmeister, K., Breen, J., Jirsa, J., Kreger, M., Detailing in structural concrete. Center for Transportation Research, Report, 1993.
89. [89] MacGregor, J.G., Wight, J.K., Teng, S., Irawan, P., Reinforced concrete: mechanics and design Upper Saddle River, NJ, Prentice Hall, 1997.
90. [90] Özkılıç, Y.O., A new replaceable fuse for moment resisting frames, Replaceable bolted reduced beam section connections, Steel and Composite Structures, 35, 353-70, 2020.
91. [91] Dere, Y., Assessing a Retrofitting Method for Existing RC Buildings with Low Seismic Capacity in Turkey, Journal of Performance of Constructed Facilities, 31, 04016098, 2016.
92. [92] Hognestad, E., A Study of combined bending and axial load in reinforced concrete members [Doctoral Thesis], University of Illinois, Urbana, University of Illinois at Urbana Champaign, College of Engineering, 1951.
93. [93] Obaidat, Y.T., Heyden, S., Dahlblom, O., The effect of CFRP and CFRP/concrete interface models when modelling retrofitted RC beams with FEM, Composite Structures, 92, 1391-8, 2010.
94. [94] Behfarnia, K., Shirneshan, A., A numerical study on behavior of CFRP strengthened shear wall with opening. Comput Concrete, 19, 179-89, 2017.
95. [95] Sümer, Y., Aktaş, M., Defining parameters for concrete damage plasticity model, Challenge Journal of Structural Mechanics, 1, 149-55, 2015.
96. [96] Tahnat, YBA., Dwaikat, M.M., Samaaneh, M.A., Effect of using CFRP wraps on the strength and ductility behaviors of exterior reinforced concrete joint, Composite Structures, 201, 721-39, 2018.
97. [97] Zhang, D., Wang, Q., Dong, J., Simulation study on CFRP strengthened reinforced concrete beam under four-point bending, Computers and Concrete, 17, 407-21, 2016.
98. [98] Hashin, Z., Failure criteria for unidirectional fiber composites. Journal of applied mechanics, 47, 329-34, 1980.
99. [99] Arduini, M., Nanni, A., Di Tommaso A., Focacci, F., Shear response of continuous RC beams strengthened with carbon FRP sheets, Non-Metallic (FRP) Reinforcement for Concrete Structures, Proceedings of the Third Symposium, 459-66, 1997.
100. [100] Kachlakev, D., McCurry, D., Behavior of full-scale reinforced concrete beams retrofitted for shear and flexural with FRP laminates, Composites Part B: Engineering, 31, 445-52, 2000.
101. [101] Lesani, M., Bahaari, M., Shokrieh, M., Numerical investigation of FRP-strengthened tubular T-joints under axial compressive loads, Composite Structures, 100, 71-8, 2013.
102. [102] Lesani, M., Bahaari, M., Shokrieh, M., Experimental investigation of FRP-strengthened tubular T-joints under axial compressive loads, Construction and building materials, 53, 243-52, 2014.
103. [103] Lesani, M., Bahaari, M., Shokrieh, M., FRP wrapping for the rehabilitation of Circular Hollow Section (CHS) tubular steel connections, Thin-Walled Structures, 90, 216-34, 2015.
104. [104] Rasheed, H.A., Larson, K.H., Amiri, S.N., Analytical solution of interface shear stresses in externally bonded FRP-strengthened concrete beams, Journal of Engineering Mechanics, 139, 18-28, 2011.
105. [105] Zhang, H., Huang, Y., Yang, Z., Xu, S., Chen, X., A discrete-continuum coupled finite element modelling approach for fibre reinforced concrete, Cement and Concrete Research, 106, 130-43, 2018.
106. [106] Qureshi, J., Lam, D., Behaviour of headed shear stud in composite beams with profiled metal decking, Advances in Structural Engineering, 15, 1547-58, 2012.
107. [107] Panigrahi, S.K., Deb, A., Bhattacharyya, S.K., Modes of Failure in Shear Deficient RC T-Beams Strengthened with FRP, Journal of Composites for Construction, 20:, 04015029, 2016.
108. [108] AASHTO., Guide Specifications for Horizontally Curved Steel Girder Highway Bridges, With Design Examples for I-girder and Box-girder Bridges, Washington, DC, American Association of State Highway and Transportation Officials, 2003.
109. [109] Müsevitoğlu, A., Arslan, M.H., Aksoylu, C., Özkış, A., Experimental and analytical investigation of chemical anchors’s behaviour under axial tensile, Measurement. 158, 107689, 2020.
110. [110] Mansur, M., Tan, K-H., Wei, W., Effects of creating an opening in existing beams, Structural Journal, 96, 899-905, 1999.
111. [111] Abdalla H, Torkey A, Haggag H, Abu-Amira A. Design against cracking at openings in reinforced concrete beams strengthened with composite sheets, Composite Structures, 60, 197-204, 2003.
112. [112] Kalfat, R., Al-Mahaidi, R., Smith, S.T., Anchorage devices used to improve the performance of reinforced concrete beams retrofitted with FRP composites, State-of-the-art review, Journal of Composites for Construction, 17, 14-33, 2013.
113. [113] Grelle, S.V., Sneed, L.H., Review of anchorage systems for externally bonded FRP laminates, International Journal of Concrete Structures and Materials, 7, 17-33, 2013.
114. [114] Adhikary, B.B., Mutsuyoshi, H., Behavior of concrete beams strengthened in shear with carbon-fiber sheets, Journal of Composites for Construction, 8, 258-64, 2004.
115. [115] Siddika, A., Al Mamun, M.A., Alyousef, R., Amran, Y.M., Strengthening of reinforced concrete beams by using fiber-reinforced polymer composites, A review. Journal of Building Engineering, 100798, 2019.
116. [116] Madenci, E., Özkılıç, Y. O., & Gemi, L. (2020). Buckling and free vibration analyses of pultruded GFRP laminated composites: Experimental, numerical and analytical investigations. Composite Structures, 254, 112806.
117. [117] Aksoylu, C., Yazman, Ş., Özkılıç, Y. O., Gemi, L., & Arslan, M. H. (2020). Experimental analysis of reinforced concrete shear deficient beams with circular web openings strengthened by CFRP composite. Composite Structures, 249, 112561.
118. [118] Madenci E, Özkılıç YO, Gemi L. Theoretical Investigation on Static Analysis of Pultruded GFRP Composite Beams. Academic Platform Journal of Engineering and Science. 2020; 8(3): 483-489.