Shear correction factors and an energy-consistent beam theory

Abstract Presented here is a new derivation of shear correction factors for isotropic beams by matching the exact shear stress resultants and shear strain energy with those of the equivalent first-order shear deformation theory. Moreover, a new method of deriving in-plane and shear warping functions from available elasticity solutions is shown. The derived exact warping functions can be used to check the accuracy of a two-dimensional sectional finite-element analysis of central solutions. The physical meaning of a shear correction factor is shown to be the ratio of the geometric average to the energy average of the transverse shear strain on a cross section. Examples are shown for circular and rectangular cross sections, and the obtained shear correction factors are compared with those of Cowper (1966) . The energy-averaged shear representative is also used to derive Timoshenkos beam theory.

[1]  Ali H. Nayfeh,et al.  A fully nonlinear theory of curved and twisted composite rotor blades accounting for warpings and three-dimensional stress effects , 1994 .

[2]  Charles W. Bert,et al.  Simplified Analysis of Static Shear Factors for Beams of NonHomogeneous Cross Section , 1973 .

[3]  G. Cowper The Shear Coefficient in Timoshenko’s Beam Theory , 1966 .

[4]  Ahmed K. Noor,et al.  Assessment of Shear Deformation Theories for Multilayered Composite Plates , 1989 .

[5]  J. N. Reddy,et al.  A higher-order shear deformation theory of laminated elastic shells , 1985 .

[6]  S. Timoshenko,et al.  Theory of Elasticity (3rd ed.) , 1970 .

[7]  Ali H. Nayfeh,et al.  A refined nonlinear model of composite plates with integrated piezoelectric actuators and sensors , 1993 .

[8]  J. Whitney Structural Analysis of Laminated Anisotropic Plates , 1987 .

[9]  T. Chow,et al.  On the Propagation of Flexural Waves in an Orthotropic Laminated Plate and Its Response to an Impulsive Load , 1971 .

[10]  Stanley B. Dong,et al.  On a Laminated Orthotropic Shell Theory Including Transverse Shear Deformation , 1972 .

[11]  Perngjin F. Pai,et al.  A new look at shear correction factors and warping functions of anisotropic laminates , 1995 .

[12]  A. Love A treatise on the mathematical theory of elasticity , 1892 .

[13]  Y. Stavsky,et al.  Elastic wave propagation in heterogeneous plates , 1966 .

[14]  M. Borri,et al.  Anisotropic beam theory and applications , 1983 .

[15]  J. Whitney,et al.  Shear Correction Factors for Orthotropic Laminates Under Static Load , 1973 .