Efficiency of steel fibers on shear strength of wide-shallow beams
Article Sidebar
Main Article Content
Abstract
Wide-shallow beams (WSBs) are structural elements characterized by having a width larger than its depth. They have special application on structures where beams must have the same thickness than the floor due to architectural requirements. Maximum spacing of shear reinforcement legs shall be provided to meet minimum shear reinforcement, restrain the growth of inclined cracking and improve ductility of the beam. As it depends on the effective height, WSBs usually require closer stirrup spacing, leading to high transverse reinforcement ratio. Steel fibers can be used in reinforced concrete beams to increase shear strength and even replace stirrups. However, most studies about the subject does not apply or is only partially related to WSBs. In this study, ten simply-supported WSBs were tested under a four-point loading system to investigate their shear behavior. Beams, with a total depth of 100 mm, width of 150 mm and 650 mm span, were cast with different amounts of steel fibers (0, 25, 35 and 45 kg/m³). Moreover, beam with minimum amount of transverse shear reinforcement were also produced. The main effects of the fibers, even in small amounts, were providing a flexural residual strength to the concrete and increasing the shear strength of the WSBs, delaying the diagonal shear crack development. The behavior of 45 kg/m³ steel fibers WSBs was significantly modified in relation to the beam without shear reinforcement. Most of the analytical models studied showed a good estimate (about 11% higher than the experimental value) of the shear strength of the WSBs analyzed.
Downloads
Article Details
This work is licensed under a Creative Commons Attribution 4.0 International License.
• The author (s) warrant that the contribution is original and unpublished and that it is not in the process of being evaluated in other journal (s);
• The journal is not responsible for the opinions, ideas and concepts issued in the texts, as they are the sole responsibility of the author (s);
• Publishers have the right to make textual adjustments and to adapt the article to the rules of publication.
Authors retain the copyright and grant the journal the right of first publication, with the work simultaneously licensed under the Creative Commons Attribution License, which allows the sharing of work with acknowledgment of authorship and initial publication in this journal.
Authors are authorized to take additional contracts separately, for non-exclusive distribution of the version of the work published in this journal (eg publish in institutional repository or as book chapter), with acknowledgment of authorship and initial publication in this journal.
Authors are allowed and encouraged to publish and distribute their work online (eg in institutional repositories or on their personal page) at any point before or during the editorial process, as this can generate productive changes as well as increase the impact and citation of the published work (See The Effect of Free Access) at http://opcit.eprints.org/oacitation-biblio.html
References
ACI COMMITTEE 544. ACI 544.1R-96: Report on Reinforced Concrete (Reapproved 2009). ACI, 2009.
AL-ZAID, R. A.; EL-SAYED, A. K.; AL-NEGHEIMISH, A. I.; SHURAIM, A. B.; ALHOZAIMY, A. M. Strengthening of structurally damaged wide shallow RC beams using externally bonded CFRP plates. Latin American Journal of Solids and Structures, v. 11, n. 6, nov. 2014.
AMIN, A.; GILBERT, R. I. Steel Fiber-Reinforced Concrete Beams—Part II: Strength, Ductility, and Design. ACI Structural Journal, v. 116, n. 2, p. 113-123, mar. 2019.
ARSLAN, G. Shear Strength of Steel Fiber Reinforced Concrete (SFRC) Slender Beams. KSCE Journal of Civil Engineering, v. 18, n. 2, p. 587-594, mar. 2014.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 16889: Concreto - Determinação da consistência pelo abatimento do tronco de cone. Rio de Janeiro, 2020.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 16935: Projeto de estruturas de concreto reforçado com fibras - Procedimento. Rio de Janeiro, 2021.
ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 6118: Projeto de estruturas de concreto - Procedimento. Rio de Janeiro, 2004.
BAẐANT, Z. P.; KIM, J. K. Size Effect in Shear Failure of Longitudinally Reinforced Beams. ACI Journal, Proceedings, v. 81, n. 5, p. 456-468, set.-out. 1984.
CASANOVA, P.; ROSSI, P.; SCHALLER, I. Can Steel Fibers Replace Transverse Reinforcements in Reinforced Concrete Beams? ACI Materials Journal, v. 94, n. 5, p. 341-354, set.-out. 1997.
CHOI, K-K.; PARK, H-G.; WIGHT, J. K. Shear strength of steel fibre-reinforced concrete beams without web reinforcement. ACI Structural Journal, v. 104, n. 1, p. 12-21, jan.-fev. 2007.
CONFORTI, A.; CUENCA, E.; MINELLI, F.; PLIZZARI, G. A. Can we mitigate or eliminate size effect in shear by utilizing steel fibers? Fib Symposium “Concrete engineering for excellence and efficiency”, Prague, Czech Republic; 2011.
CONFORTI, A.; MINELLI, F.; PLIZZARI, G. A. Wide-shallow beams with and without steel fibres: A peculiar behaviour in shear and flexure. Composites: Part B, v. 51, p. 282-290, Elsevier, ago. 2013.
CUENCA, E.; SERNA, P. Failure modes and shear design of prestressed hollow core slabs made of fiber-reinforced concrete. Composites Part B: Engineering, v. 45, n. 1, p. 952-964, fev. 2013.
DINH, H. H.; PARRA-MONTESINOS, G. J.; WIGHT, J. K. Shear Behavior of Steel Fiber-Reinforced Concrete Beams without Stirrup Reinforcement. ACI Structural Journal, v. 107, n. 5, p. 597-606, set.-out. 2010.
IMAM, M.; VANDEWALLE, L.; MORTELMANS, F.; VAN GEMERT, D. Shear domain of fibre reinforced high-strength concrete beams. Engineering Structures, v. 19, n. 9, p. 738-747, set. 1997.
ISMAIL, M., K.; YOSRI, A.; EL-DAKHAKHNI, W. A Multi-Gene Genetic Programming Model for Predicting Shear Strength of Steel Fiber Concrete Beams. ACI Structural Journal. v. 119, n. 2, mar. 2022.
JAPAN SOCIETY OF CIVIL ENGINEERS. JSCE-SF4: Method of tests for flexural strength and flexural toughness of steel fiber reinforced concrete. Concrete Library of JSCE. Part III-2 Method of tests for steel fiber reinforced concrete, n. 3, p. 58-61, jun. 1984.
JUÁREZ, C.; VALDEZ, P.; DURÁN, A.; SOBOLEV, K. The diagonal tension behavior of fiber reinforced concrete beams. Cement and Concrete Composites, v. 29, n. 5, p. 402-408, mai. 2007.
KHALIL, A. E.; ETMAN, E.; ATTA, A.; BARAGHITH, A.; BEHIRY, R. The Effective Width in Shear Design of Wide-shallow Beams: A Comparative Study. KSCE Journal of Civil Engineering, v. 23, p. 1670-1681, fev. 2019.
LANTSOGHT, E. O. L. Database of Shear Experiments on Steel Fiber Reinforced Concrete Beams without Stirrups. Materials, v. 12, n. 917, mar. 2019.
MONDO, E. Shear Capacity of Steel Fibre Reinforced Concrete Beams Without Conventional Shear Reinforcement. Dissertação (Mestre das ciências). Royal Institute of Technology, Stockholm: MoST, Sweden, 2011.
NARAYANAN, R.; DARWISH, I. Y. S. Use of steel as shear reinforcement. ACI Structural Journal, v. 84, n. 3, p. 216-227, mai.-jun. 1987.
SHURAIM, A. B., AL-NEGHEIMISH, A. I. Design considerations for joist floors with wide-shallow beams. ACI Structural Journal, v. 108, n. 2, p. 188-196, mar.-abr. 2011.
SINGH, H. Steel Fiber Reinforced Concrete: Behaviour, Modelling and Design. Editora Springer. Singapore: Springer Nature, 2017.
ZARARIS, P. D.; PAPADAKIS, G. CH. Diagonal shear failure and size effect in RC beams without web reinforcement. Journal of Structural Engineering, v. 127, n. 7, jul. 2001.
ZSUTTY, T. Shear Strength Prediction for Separate Categories of Simple Beam Tests. ACI Journal, Proceedings, v. 68, n. 2, p.138-143, fev. 1971.