Calculation of Voided Slabs Rigidities

A theoretical study of the rigidities of slabs with circular voids oriented in the longitudinal and in the transverse direction is discussed. Equations are presented for predicting the bending and torsional rigidities of the voided slabs. This paper summarizes the results of an extensive literature search and initial review of the current methods of analyzing voided slab. The various methods of calculating the equivalent plate parameters, which are necessary for two-dimensional analysis, are also reviewed. Static deflections on voided slabs are shown to be in good agreement with proposed equation.

Authors:

• Gee-Cheol Kim
• Joo-Won Kang

Keywords:

• voided slab
• bending rigidity
• torsional rigidity
• orthotropic plate

References:

[1] H. Aster, The Analysis of Rectangular Hollow RC Slabs Supported on
Four Sides., Approved doctoral thesis, Technological University of
Stuttgart, Germany, 1968
[2] J. C. Jofriet, G. M. McNeice and P. Csagoly, "Finite Element Analysis of
Prestressed Concrete Voided Bridge Decks," PCI Journal May/June, 1973.
PP. 51´¢×66, 1973
[3] R.P. Pama, S.Imsom-Somboon and S.L. Lee, "Elastic Rigidities of
Circularly Voided Slabs," Build. Sci., Vol. 10, pp. 207´¢×212, 1975
[4] B. Bakht, L.G. Jaeger, M.S. Cheung and A.A. Mufti, "The State of the art
in Analysis of Cellular and Voided Slab Bridge," Can. J. Civ. Eng., Vol.
8, pp. 376´¢×391, 1981
[5] G. Elliott and L.A. Clark, "Circular Voided Concrete Slab Stiffnesses,"
Journal of Structural Division, Vol. 108, No. 11, pp. 2379´¢×2393, 1982
[6] Ansel C. Ugural, Stresses in Plates and Shells(2nd), 1999
[7] P.C.J Hoogenboom, "Analysis of hollow-core slab floors," HERON Vol.
50, No.3, pp.173-185, 2005,
[8] Neil M. Hawkins, S. K. Ghosh, "Shear Strength of Hollow-Core Slabs, "
PCI Journal, 2, 2006
[9] Ontario Highway Bridge Design Code. 1979. Ontario Ministry of
Transportation and Communications, Ont.
[10] Gee-Cheol Kim, G-H Choi and Dong-Guen Lee, "Modeling of Walking
Loads for Floor Vibration Analysis", Journal of the Computational
Structural Engineering Institute of Korea, Vol. 15, No. 1, pp. 173´¢×188,
2002.
[11] Y.G. Park, H.S. Kim, H. Ko, H.J Park and D.G. Lee, , "Evaluation of The
Nonlinear Seismic Behavior of a Biaxial Hollow Slab," Journal of EESK,
Vol. 15, No.1, pp.1-10, 2011