Experimental Time-Dependent Deflection of High Strength Concrete Panels

Bayan S. Al Numan^1, , Faris R. Ahmed² and Zahraa N. Rashied³

¹Civil Engineering Department, Faculty of Engineering, Ishik University, Erbil, Iraq

²Civil Engineering Department, Faculty of Engineering, Koya University, Erbil, Iraq

³Geotechnical Engineering Department, Faculty of Engineering, Koya University, Erbil, Iraq

Cite this paper:
Bayan S. Al Numan, Faris R. Ahmed and Zahraa N. Rashied. Experimental Time-Dependent Deflection of High Strength Concrete Panels. American Journal of Civil Engineering and Architecture. 2015; 3(5):153-157. doi: 10.12691/ajcea-3-5-1

Abstract

This work presents an experimental study on both short-term and long-term deflections for a period more than seven months of reinforced high and normal strength reinforced concrete two-way flat plate panels. Four reinforced concrete panels with dimensions of (960×960×50) mm were investigated with simply supported edges. Concrete cube strength is about 75 MPa for HSC panels, and 30 MPa for the control panel. Sustain load kept along the entire test period and at the end, the loads is removed and the recoverable deflection was measured. It’s been concluded that the rate of increase in HSC panels’ long time deflection is less than that of NSC panels, also the long-term deflection is highly reduced by increasing the compressive strength of concrete and the long term deflection reduced about 20% when compressive strength increased from 25 to 65 MPa.

Keywords:
concrete panels high strength Two-Way Slab Long and Short -Term Deflection

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References:

[1]	ACI Code (31814), “Building Code Requirements for Reinforced Concrete”, American Concrete Institute, Detroit, Mich. 2002.
[2]	Edwrd G. Nawy, “High Performance concrete”, John Wiley & Sons, Inc., Second Edition, 2001.
[3]	Ali, F.A., Abu-Tair, A., O'Connor, D., Benmarce, A. and Nadjai A., “Useful and Practical Hints on the Process of Producing High-Strength concrete”, Practical Periodical on Structural Design and Construction, Nov., 2001.
[4]	AS3600-1994, Australian Standard for Concrete Structures, Standards Australia, Sydney, (1994).
[5]	R.I. Gilbert, “Shrinkage, Cracking and Deflection; the Serviceability of Concrete Structures”, Electronic Journal of Structural Engineering, 2001.
[6]	Stokal S., “Strength of Concrete under Uniaxial Sustained Loading”, SP-34 Concrete for Nuclear Reactors, Vol.1, 1972, pp. 313-326.
[7]	Samir A. Ashour and Khalid Mahmood, “Long-Term Deflection of High-Strength Fiber Reinforced Concrete Beams”, Structural Engineering and Mechanics, An International Journal, Vol.8, No.6, 1999, pp.236-246.
[8]	Ghali, A., “Deflection of Reinforced Concrete Members: A Critical Review”, ACI Structural Journal, Vol.90, No.4, July-August 1993, pp.364-373.
[9]	Hall, T., and Ghali, A., “Long - Term Deflection of Concrete Members Reinforced with Glass Fiber Reinforced Polymer Bars”, Canadian Journal of Civil Engineering, 2000, (Internet Paper).
[10]	Jawad, F.A.F., “Long-Term Deflection of Two-Way Slab Systems: with Particular Focus on Iraqi Practice”, M.Sc. Thesis, College of Engineering, Al-Mustansiriyah University, Baghdad, Iraq, February 2000, 143p.
[11]	Iraqi Specifications No. (5), 1984 for Portland Cement.
[12]	Iraqi Specifications No. (45), 1984 for Aggregates of Natural Resources used for Concrete and Construction.
[13]	ACI 211.4R-93 “Guide for Selecting Proportions for High-Strength Concrete With Portland Cement and Fly Ash”, ACI Manual of Cement Practice, Part 1: Materials and General properties of concrete, PP.(13), Detroit ,Michigan 1994.
[14]	Figarovskij, V. V., “Experimental Investigation of Stiffness and Cracking of Reinforced Concrete Flexural Members Subjected to Short-Term and Long-Term Loading”, Ph.D. Thesis (in Russian), Moscow, 1962.
[15]	Hend K.S. Al-Kubaisy, “Short and Long-Term Deflections of Reinforced Polymer Modified Concrete Panels”, M.Sc. Thesis, College of Engineering, Al-Mustansiriyah University, Baghdad, Iraq, Dec 2004.
[16]	Neville, A. M. “Properties of Concrete” Pitman publishing Limited, London's 4th Edition 2000, PP. (674-760).
[17]	Branson D.E, “Deformation of Concrete Structures”, McGraw-Hill Book Company, 1977, 546 pp.