Effect of Tensile Reinforcement Ratio on the Effective Moment of Inertia of Reinforced Lightweight Concrete Beams for Short Term Deflection Calculation
DOI:
https://doi.org/10.5614/itbj.eng.sci.2011.43.3.4Abstract
This paper presents an improvement model of the effective moment of inertia to predict the short term deflection of reinforced lightweight concrete beam. The models were developed using 9 beams of reinforced pumicelightweight concrete tested under two symmetrical-point loads. The presence of steel reinforcement in the beam was taken into consideration in the developed model. The models were verified by test carried out on other 9 beams. Those beams subjected to various-point loads and compressive strength. The results of investigation revealed that crack moment of inertia increased with the increased tensile reinforcement ratio. Thus, the reinforcement ratio significantly affects the value of effective moment of inertia of reinforced lightweight concrete beam. All the beam test results produced considerable deflection in comparison to that obtained using current Codes either ACI or SNI. The proposed model demonstrated a good agreement to the experimental results and in some cases have similar trend to that of the ACI or SNI prediction.
Downloads
References
Sugiharto, H., Prasetyo, A., Ary, F., P., Studi Penggunaan Batu Apung Untuk Beton Ringan Sebagai Komponen Struktural, Laporan Penelitian No.01/Pen/SIPIL/1997, UK Petra, Surabaya, 1997.
ASTM C330-89, Standard Specification for Lightweight Aggregate for Struktural Concrete, Annual Book of ASTM Standards, 4(2), 1992.
SNI 03-2847-2002, Tata Cara Penghitungan Struktur Beton untuk Bangunan Gedung, Badan Penerbit Pekerjaan Umum, Jakarta Selatan, 2002.
Rossignolo, J.A. & Agnesini, M.V.C., Durability of polymer-modified lightweight aggregate concrete, Cement and Concrete Composite, 26, pp. 375-380, 2004.
Haque, M.N., Al-Khaiat, H. & Kayali, O., Strength and Durability of Lightweight Concrete, Cement & Composite Concrete, 26, pp. 307-314, 2004.
Owens, P.L., Structural lightweight Aggregate Concrete-the Future?, Concrete, 33(10), pp. 45-7, 1999.
ACI Committee 318, Building Code Requirement for Reinforced Concrete and Commentary (ACI 318-02/ACI 318R-02), American Concrete Institute, Detroit, pp. 103, 2002.
Branson, D.E., Instantaneous and Time dependent Deflection of simple and Continues Reinforced Concrete Beams, HPR Report No. 7, Part 1, Alabama, Highway Department/US Bureau of Public Roads, pp 1-78, 1963.
Al-Shaikh, A.H. & Al-Zaid, R.Z., Effect of Reinforcement Ratio on the Effective Moment of Inertia of Reinforced Concrete Beams, ACI Structural Journal, 90(2), pp. 144-148, 1993.
Al-Zaid, R.Z., Al-Shaikh, A.H. & Abu-Hussein, M.M., Effect of Loading Type on the Effective Moment of Inertia of Reinforced Concrete Beams, ACI Structural Journal, 88, pp. 184-190, 1991.
Ashour, S.A., Effect of Compressive strength and Tensile Reinforcement ratio on flexural behaviour of high-strength concrete beams, Engineering Structures, 22, pp. 413-423, 2000.
Ghali, A., Deflection of Reinforced Concrete Members: A Critical Review, ACI Structural Journal, 90(4), July-August, 1993, pp. 364-373, 1993.
Gilbert, R.I., Deflection Calculation for Reinforced Concrete StructuresWhy We Sometimes Get It Wrong, ACI Structural Journal, 96, pp. 1027-1032, 1999.
Gilbert, R.I., Shrinkage, Cracking and Deflection - the Serviceability of Concrete Structures, Electronic Journal of Structural Engineering, 1, pp. 15-37, 2001.
Grossman, J.S., Simplified Computations for Effective Moment of Inertia Ie and Minimum Thickness to avoid Deflection Computations, ACI Structural Journal, 78, pp. 423-439,1981.
Fikry, A.M. & Thomas, C., Development of a model for the effective moment of inertia of one-way reinforced concrete elements, ACI Structural Journal, 95(4), pp. 444-455,1998.
Akmaluddin & Thomas, C., Experimental Verification of Effective Moment of Inertia Used in the Calculation of Reinforced Concrete Beam Deflection, Proceeding of Civil Engineering Conference "Towards Sustainable Civil Engineering Practice" , Petra Christian University, Surabaya, pp. 89-98, 2006.
Almussalam, A., Beshr, H., Maslehuddin, M. & Al-Amoudi, O., Effect of Silica Fume on the Mechanical properties of Low quality Coarse Aggregate Concrete, Cement & Composite Concrete, 26, pp. 891-900, 2004.
Campione, G. & Mendola, La L., Behaviour in Compressions of Lightweight fibre Reinforced Concrete with Transverse Steel Reinforcement, Cement & Composite Concrete, 26, pp. 645-656, 2004.
ASTM C39-86, Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens, Annual Book of ASTM Standards, 4(2),1992.
ASTM C-469, Standard Test Method for Static Modulus of Elasticity and Poisson's Ratio of Concrete in Compression, Annual Book of ASTM Standards, 4(2),1992.
Kuang, K.S.C., Akmaluddin, Cantwell, W.J. & Thomas C., Crack Detection and Vertical Deflection Monitoring in Concrete Beams Using Plastic Optical Fibre Sensors, Measurement Science and Technology, 14, pp. 205-216, 2003.
