The Behavior of Punching Shear Strength on Geo-Polymer Concrete Circular Slabs with Openings: A Review
Main Article Content
Abstract
This paper examines eco-friendly concrete, focusing specifically on geopolymer concrete and its performance in reinforced concrete circular slabs, with and without openings, as well as its strength when reinforced with CFRP sheets under punching shear conditions. Flat reinforced concrete slabs are frequently utilized in construction due to their efficiency and speed of installation, along with the continuous smoothness achieved in the arrangement of the elements. However, slab systems often lack adequate shear strength in both directions. As a result, they may suffer shear failure at the points where they intersect with columns, leading to the failure of a larger segment of the structure. Various factors can contribute to shear failure, including changes in the usage of the facility, design and construction errors, increased load, material degradation, and poor-quality standards. The placement of openings can occur in either the positive or negative moment area of the slab, giving rise to different challenges that cannot be addressed with a uniform approach. To correct structural deficiencies, carbon fiber-reinforced polymer (CFRP) sheets or strips are utilized as composite elements. The application of CFRP improves the punching shear resistance in both directions and also enhances flexural strength, ductility, and rigidity. This makes CFRP a more feasible option compared to other costly and complex methods, such as increasing the cross-sectional dimensions of columns. This paper reviews recent research on the application of Carbon Fiber Reinforced Polymer (CFRP) to boost the shear strength of flat slabs. It details the materials used for the reinforcement of these slabs and the techniques employed in their application. Furthermore, the paper summarizes the studies cited and proposes possible directions for future research.
Article Details

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Licensed under a CC-BY license: https://creativecommons.org/licenses/by-nc-sa/4.0/
How to Cite
References
Ying, T., “Behavior and Modeling of Reinforced Concrete Slab-Column Connections”, Ph.D. Thesis, The University of Texas at Austin, May, 2007.
J.G. MacGregor, J.K. Wight, Reinforced Concrete Mechanics and Design (4th 15 Edition), 2004.
Lateef S. Lateef, Saad Khalaf Mohaisen
“RC Flat Slab with Opening Strengthened Embedded Bearing Plateunder Punching Shear” Al-Rafidain Journal of Engineering Sciences Vol. 2, Issue 2, 2024: 08-15
Zahraa Maitham, Ali Sabah “Punching Shear Behavior for Flat Slabs with CFRP and Openings” Al-Rafidain Journal of Engineering Sciences Vol. 2, Issue 2, 2024: 362-373
Moe, J. “Shearing Strength of Reinforced Concrete Slabs and Footings Under Concentrated Loads”, Portland Cement Association, Research and Development Laboratories, Bulletin D47, April 1961.
Aalami, B.O., "Design of Post Tensioned Floor Slabs", Concrete International, Vol.11, No.6, June (1989), PP. 59-67.
BarisBinici, “Punching Shear Strengthening of Reinforced Concrete Slabs Using Fiber Reinforced Polymers”, Ph.D Thesis, The University of Texas at Austin, December 2003.
Schanerch D., Standford, K. and Lanier, B., “Use of High ModulusCarbon Fiber Reinforced Polymer (CFRP) for Strengthening Steel Structures”, Department of Civil Construction and Environmental Engineering, North Carolina State University,U.S.A., 2001. Cited by RadhwanAbdulsattar Abbas, “Nonlinear Analysis of Reinforced Concrete Beams Strengthened With Carbon Fiber Polymer”, M.Sc.Thesis, Al-Nahrain University, 2009.Hardjito, D., Wallah, S., Sumajouw, D. M. J. and Rangan, B. V., "On the Development of Fly Ash–Based Geopolymer Concrete". ACI Materials Journal, vol. 101, no. 6, pp 467–472, 2004
J. Davidovits," Geopolymer: Chemistry & Applications", 4th ed., no. October. Saint-Quentin: Geopolymer Institute, 2008.
Kong D.L.Y., Sanjayan J.G., Damage behavior of Geopolymer composites exposed to elevated temperature, Cement and Concrete Composites, Vol. 30, pp.986-991, 2008.
Hardjito D, Wallah SE, Sumajouw DMJ, Rangan BV. On the development of fly ash-based geopolymer concrete ACI Materials Journal. 2004; 101:467-72.
G. Concrete, "Low-Calcium, Fly-Ash-Based Geopolymer Concrete", pp. 1– 21, 2010.
J. Davidovits, "Properties of Geopolymer Cements", First Int. Conf. Alkaline Cement. Concrete. pp. 131–149, 1994.
E. Gartner, "Industrially interesting approaches to low- CO2", Cement Concrete. Res, vol. 34, no. 9, pp. 1489–1498, Sep. 2004.
Vasques, A., and Karbhari, V. M., “Fiber reinforced polymer composite strengthening of concrete slabs with cutouts,” ACI Struct. J., V.100, No. 5, Sept.-Oct. 2003, pp. 665-673.
Provis, J.L. and Van Deventer, J.S.J. eds., " Geopolymers: structures, processing, properties, and industrial applications", Elsevier, 2009
Davidovits, J., " Geopolymers: man-made rock geosynthesis and the resulting development of very early high strength cement", Journal of Materials education, 16, pp.91-91, 1994.
Plus, M.T., "Environmental implications of Geopolymers", 2013.
Hanjitsuwan, S., Hunpratub, S., Thongbai, P., Maensiri, S., Sata, V. and Chindaprasirt, P., "Effects of NaOH concentrations on physical and electrical properties of high calcium fly ash geopolymer paste" Cement and Concrete Composites, 45, pp.9-14, 2014.
Duxson, P., Fernández-Jiménez, A., Provis, J.L., Lukey, G.C., Palomo, A. and van Deventer, J.S., Geopolymer technology: the current state of the art. Journal of materials science, 42(9), pp.2917-2933, 2007.
Pacheco-Torgal, F., Castro-Gomes, J. and Jalali, S., "Alkali-activated binders: A review: Part 1. Historical background, terminology, reaction mechanisms, and hydration products", Construction and Building Materials, 22(7), pp.1305-1314, 2008.
Ye, N., Yang, J., Liang, S., Hu, Y., Hu, J., Xiao, B. and Huang, Q., "Synthesis and strength optimization of one-part geopolymer based on red mud", Construction and Building Materials, 111, pp.317-325, 2016.
Davidovits, J., "Geopolymers and geopolymeric materials", Journal of thermal analysis, 35(2), pp.429-441, 1989.
Davidovits, J., "Properties of geopolymer cement" In First international conference on alkaline cement and concretes (Vol. 1, pp. 131-149). Kiev State Technical University, Ukraine: Scientific Research Institute on Binders and Materials, 1994.
Motorwala, A., Shah, V., Kammula, R., Nannapaneni, P. and Raijiwala, D.B., "Alkali activated fly-ash based geopolymer concrete", International journal of emerging technology and advanced engineering, 3(1), pp.159-166, 2013.
Swanepoel, J.C. and Strydom, C.A., "Utilisation of fly ash in a geopolymeric material", Applied geochemistry, 17(8), pp.1143-1148, 2002.
Davidovits, J., "Chemistry of geopolymeric systems, the terminology", In Geopolymer (Vol. 99, No. 292, pp. 9-39), 1999.
Palomo, A., Grutzeck, M.W. and Blanco, M.T., "Alkali-activated fly ashes: A cement for the future", Cement and concrete research, 29(8), pp.1323-1329, 1999.
Fan, F., "Mechanical and thermal properties of fly ash-based geopolymer cement, 2014.
M. Ali Sadawy, Ahmed Serag Faried, and H. A. El-Ghazaly, (2020), “Influence of Various Types of Steel Fibre on the Mechanical and Physical Characteristics of GGBS Based Geopolymer Concrete”, Journal of Engineering Research andReports,12(1), 7-1
Shihab, A. M., Abbas, J. M., & Ibrahim, A. M. “Effects of temperature in different initial duration time for soft clay stabilized by fly ash based geopolymer”. Civil Engineering Journal, Vol. 4 No. 9, 20822096. (2018).
Davidovits, J., "Application of Ca-based geopolymer with blast furnace slag", a review. In 2nd International Slag Valorisation Symposium, pp. 33-49, 2011.
Blast Furnace Slag, Retrieved at (5/3/2023), from https://www.ispatguru.com/author/satyendra/.
Slag Cement Association, Retrieved at (18/6/2023), from https://www.slagcement.org/.
Karunanithi, S., "Experimental Studies on Punching Shear and Impact Resistance of Steel Fibre Reinforced Slag Based Geopolymer Concrete", Advances in Civil Engineering, 2017.
Marwa.A.Sadawy, A.Serag Faried, and H.A. El-Ghazaly, "Investigating the Impact of Punching Shear Strength on Geo-Polymer Concrete Slabs with Openings", Design Engineering, Issue: 8, pp.9148-9161, 2021.
M. Ali Sadawy, Ahmed Serag Faried, and H. A. El-Ghazaly, (2020), “Influence of Various Types of Steel Fibre on the Mechanical and Physical Characteristics of GGBS Based Geopolymer Concrete”, Journal of Engineering Research reports,12(1), 7-1
Sarwar Hasan Mohammad, Mehmet Eren Güls, and Abdulkadir Çevik, "Punching shear behaviour of geopolymer concrete two-way slabs reinforced by FRP bars under monotonic and cyclic loadings", Advances in Structural Engineering, Vol. 25(3), pp. 453–472, 2022.
Marwa.A. Sadawy, A.Serag Faried, and H.A. El-Ghazaly, Punching Shear of Reinforced Geopolymer Concrete Slabs with and without Openings: A Review, International Journal of Engineering Research & Technology (IJERT), Vol. 11 Issue 12, December 2022
Marko Bartolac, Domagoj Damjanović, Ivan Duvnjak, “Punching strength of flat slabs with and without shear reinforcement”, GRAĐEVINAR 67 - 8, 771-786, 2015.
Yaser, M., Aurelio, M., “Tests on the Post-Punching Behavior of Reinforced Concrete Flat Slabs”, Structural concrete laboratory of the Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland. October 2008. pp.1-2.
ACI CODE-318, "Building Code Requirements for Structural Concrete and Commentary" American Concrete Institute, Farmington Hill, MI, 2019.
BS 8110, ''Structural Use of Concrete, Part 1, Code of Practice for Design and Construction'', British Standards Institution, London,1997.
EC 2. Design of Concrete Structures Part I: General Rules and Buildings. European Committee for Standardization Brussels; 2002.
Zhang, X., "Punching Shear Failure Analysis of Reinforced Concrete Flat Plates Using Simplified UST Failure Criterion", M.Sc. Thesis, Griffith University, December 2002.
Alexander, S. D. B. and Simmonds, S.H., "Ultimate Strength of Slab-Column Connections", ACI Structural Journal, Vol. 34, No. 3. May-June 1987, PP. 255-261.
EN 1992-1-1: Eurocode 2: "Design of Concrete Structures"-Part 1-1: "General Rules and Rules for Buildings"; British Standard Institution: London, UK, 2004.
Genikomsou, A.; Polak, M.A. "Finite Element Simulation of Concrete Slabs with various Placement and Amount of Shear Bolts". Procedia Eng. 2017, 193, 313–320.
Yooprasertchai, E. Y. Tiawilai, T. Wittayawanitchai, J. Angsumalee, P. Joyklad, Q. Hussain, "Effect of Shape, Number, and Location of Openings on Punching Shear Capacity of Flat Slabs" Buildings, vol.11, no.10, p.484,2021.
El-Salakawy, E. F., Polak, M.N., and Soliman, M.H, "Reinforced Concrete Slab-Column Edge Connection with Openings", ACI Structural Journal 1999, Vol. 96, No. 1, January, PP. 79-87.
Guan, H., "Prediction of Punching Shear Failure Behavior of Slab-Edge Column Connections with Varying Opening and Column Parameters". Advances in Structural Engineering-An International Journal 2009, Vol. 12, No.1, pp. 19-36.
Al-Shammari A.H." Effect of Openings with or without Strengthening on Punching Shear Strength for Reinforced Concrete Flat Plates" Journal of Engineering Number2 Volume 17 April 2011.
Ridha Z. M. "Experimental Study of Punching Shear Strength of Self-Compacting Concrete Slabs with Openings" Journal of Kerbala University, Vol. 9 No.2 Scientific. 2011.
Oukaili, S. "Punching Shear Strength of Reinforced Concrete Flat Plates with Openings" Journal of Engineering No.1 Vol. 20, January 2014.
K. Brosens, “Strengthening of Concrete Structures with Externally Bonded Reinforcement-Design philosophy and practical applications”, Leuven University, Belgium, 1999.
D.Gemert, “Strengthening of Concrete Structures with Externally Bonded Reinforcement-Design philosophy and practical applications”, Leuven University, Belgium. 2000.
A. Nanni and T. Iball, "Experimental results of Two-way slabs with openings strengthened with CFRP laminates ", Accepted to a sixth international symposium on Fiber Reinforced Polymer Reinforcement of Reinforced Concrete structures, Singapore, 2003.
O.Enochsson, "CFRP Strengthening of Concrete Slabs with and without Openings”, M. Sc. Thesis, Lulea University of Technology, Lulea, Sweden, 2005.
H.T.N. Al-Wetaifi, “Evaluation of the Behavior of Two-Way R.C. Slabs with Openings Strengthen with CFRP”, M.Sc. Thesis, University of Babylon, Iraq, August, 2009.
W.E. Elsayed, U.A. Ebead and W. Neale “Mechanically fastened FRP-strengthened two-way concrete slabs with and without cutouts”.
J Compos Construct, p.p :198–207, 2009. 00
L. M. A.Shather, “Experimental and Theoretical Investigation into Concrete Slabs with Opening Reinforced with CFRP Bars”, Ph.D. Thesis, University of Basrah, 2011.
N. Mohammed “Experimental study of self-compacting RC slabs with opening strengthening with carbon fiber laminated and steel fiber”, J Eng Dev;16(1):54–74,2012.
B. J. Al-Sulayvani, D. N. Al-Talabani, “Strengthening of Circular RC Slabs with Central Openings Using CFRP Strips under Repeated Loading “Department of Civil Engineering, University of Mosul, Mosul, Iraq, 2014.
H. A. Abed, “CFRP Strengthening of Reinforced Concrete Slabs with Openings” M. Sc. The University of Babylon, 2015.
S. S. Aman, B. S. Mohammed, M. A. Wahab, and A. Anwar, “Performance of Reinforced Concrete Slab with Opening Strengthened Using CFRP," Fibers, vol. 8, no. 4, Apr. 2020, Art. no. 25, https://doi.org/10.3390/fib8040025.