Steel Fiber Enhancement upon Punching Shear Strength of Concrete Flat Plates Exposed to Fire Flame

Ahmed Naji Dalaf, Shatha Dheyaa Mohammed

Abstract


In this study, the effect of fire flame on the punching shear strength of steel fiber reinforced concrete flat plates was experimentally investigated using nine half-scale specimens with dimensions of 1500×1500 mm and a total thickness of 100 mm. The main investigated variables comprised the steel fiber volume fraction 0, 1, and 1.5% and the burning steady state temperature 500 and 600 °C. The specimens were divided into three groups, each group consists of three specimens. The specimens in the first group were tested with no fire effect to be the reference specimens, while the others of the second and third groups were tested after being exposed to fire-flame effect. The adopted characteristics of the fire test were; (one hour) burning time duration and 500 and 600 °C steady state temperature with sudden cooling process (water sprinkling directly after burning). The test results proved that exposing to direct fire effect for one hour caused a reduction in the punching shear strength with an increase in the ultimate mid-span deflection. Also, it was noticed that using steel fiber in the concrete mix leads to a significant increase in the punching shear strength for both the unburned and burned specimens. The ultimate punching load increased by about 11 and 16.6% for the unburned specimens with 1.0 and 1.5% steel fiber volume fraction, respectively, and by about 22.4 and 19% for the burned specimens at 500 °C with 1.0 and 1.5% steel fiber volume fraction, respectively. While, it was increased by about 29.2 and 21.5% for the burned specimens at 600 °C with 1.0 and 1.5% steel fiber volume fraction, respectively, as compared with the reference specimen of each group.

 

Doi: 10.28991/cej-2021-03091751

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Keywords


Punching Shear; Steel Fibers; Flat Plates; Fire.

References


Osman. M, Marzouk. H. and Helmy. S., “Behavior of High-Strength Lightweight Concrete Slabs Under Punching Loads.” ACI Structural Journal 97, no. 3 (2000). doi:10.14359/4644.

Pilakoutas. K. and Li. X. “Alternative Shear Reinforcement for Reinforced Concrete Flat Slabs.” Journal of Structural Engineering 129 , no. 9 (September 2003): 1164–1172. doi:10.1061/(asce)0733-9445(2003)129:9(1164).

Menétrey, Ph. “Synthesis of Punching Failure in Reinforced Concrete.” Cement and Concrete Composites 24, no. 6 (December 2002): 497–507. doi:10.1016/s0958-9465(01)00066-x.

Anas, I. Abdullah and Shatha D. Mohammed, “Structural Behavior of High Strength Laced Reinforced Concrete One Way Slab Exposed to Fire Flame.” Civil Engineering Journal 5 , no. 12 (December 2019): 2747–2761. doi:10.28991/cej-2019-03091446.

Mohammed, Shatha Dheyaa, and Nada Mahdi Fawzi. "Fire Flame Influence on the Behavior of reinforced Concrete Beams Affected by Repeated Load." Journal of Engineering 22, no. 9 (2016): 206-223.

Alexander S., and Simmonds S., “Punching Shear Tests of Concrete Slab-Column Joints Containing Fiber Reinforcement.” ACI Structural Journal 89, no. 4 (1992). doi:10.14359/3027.

Megally S and Ghali A., “Punching shear design of earthquake resistant slab-column connections.” ACI Structural Journal 97, no. 5 (September 2000): 720–730. doi:10.14359/8807.

Hamid, Hala Aqeel, and Shatha D. Mohammed. “Behavior of Reinforced Reactive Powder Concrete Two-Way Slabs Under Static and Repeated Load.” Civil Engineering Journal 4, no. 6 (July 4, 2018): 1178. doi:10.28991/cej-0309166.

Kamal, Mounir M., Mohamed A. Safan, Zeinab A. Etman, and Bsma M. Kasem. “Mechanical Properties of Self-Compacted Fiber Concrete Mixes.” HBRC Journal 10, no. 1 (April 2014): 25–34. doi:10.1016/j.hbrcj.2013.05.012.

Nguyen-Minh, L., M. Rovňák, T. Tran-Quoc, and K. Nguyenkim. “Punching Shear Resistance of Steel Fiber Reinforced Concrete Flat Slabs.” Procedia Engineering 14 (2011): 1830–1837. doi:10.1016/j.proeng.2011.07.230.

Umran, M. K. “Fire Flame Exposure Effect on Some Mechanical Properties of Concrete” M.Sc. Thesis, College of Engineering, Babylon University, Babil, Iraq (October, 2002).

Venkatesh. K, “Properties of Concrete at Elevated Temperature.” ISRN Civil Engineering 14, no. 2 (March 2014): 1–15. doi:10.1155/2014/468510.

Aboud, Rawaa K, Hadeel K Awad, and Shatha D Mohammed. “Fire Flame Effect on the Compressive Strength of Reactive Powder Concrete Using Different Methods of Cooling.” IOP Conference Series: Materials Science and Engineering 518 (June 5, 2019): 022029. doi:10.1088/1757-899x/518/2/022029.

Moss, P.J., R.P. Dhakal, G. Wang, and A.H. Buchanan. “The Fire Behaviour of Multi-Bay, Two-Way Reinforced Concrete Slabs.” Engineering Structures 30, no. 12 (December 2008): 3566–3573. doi:10.1016/j.engstruct.2008.05.028.

Salem, Hamed, Heba Issa, Hatem Gheith, and Ahmed Farahat. “Punching Shear Strength of Reinforced Concrete Flat Slabs Subjected to Fire on Their Tension Sides.” HBRC Journal 8, no. 1 (April 2012): 36–46. doi:10.1016/j.hbrcj.2011.10.001.

ACI, 318M. “Review of Building Code Requirements for Structural Concrete (ACI 318-95) and Commentary (ACI 318R-95) by ACI Committee 318.” Journal of Architectural Engineering 2, no. 3 (September 1996): 120. doi:10.1061/(asce)1076-0431(1996)2:3(120.3).

Iraq Standard Specification. IQS 5:2019. Standard specification for Portland cement. Iraq: C.O.S.Q.C; (2019).

Iraq Standard Specification. IQS 45-93. Aggregate from natural sources for concrete and building construction. Iraq: C.O.S.Q.C; (1993).

ASTM Designation C39-01, “Compressive Strength of Cylindrical Concrete Specimens”, Annual Book of ASTM Standards, American Society for Testing and Materials, Philadelphia, Pennsylvania, Section 4, V. 4.02, (2001).

ASTM C496/C496M-04, “Standard Test Method for Splitting Tensile Strength of Cylindrical Concrete Specimens”, Vol. 04. 02, (2001).

Choi, Kyoung-Kyu, Hong-Gun Park, and Hye-Min Kim. “Shear Strength Model for Slab-Column Connections.” Journal of the Korea Concrete Institute 22, no. 4 (August 31, 2010): 585–593. doi:10.4334/jkci.2010.22.4.585.


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DOI: 10.28991/cej-2021-03091751

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