Summary
This paper deals with the general case of biaxial bending of a curved beam in space whose centerline is circularly curved. Stress equations at any point in the cross-section of the beam have been derived by using Winkler's method. Neutral planes were established and stress factors were found and tabulated for variable thicknesses, widths, and ratios of (R 2/R 1). Numerical examples for several cases are solved and are demonstrated in graphical manner.
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Abbreviations
- a :
-
semi-major axis of an ellipse
- a 1 :
-
distance from the centroidal point, along they axis to the interior fiber
- a 2 :
-
distance from the centroidal point, along they axis to the exterior fiber
- A :
-
cross sectional area
- A 1 :
-
=a 2+a 1
- A 3 :
-
=a 2 3+a 1 3
- A 4 :
-
=a 2 4−a 1 4
- b :
-
semi-minor axis of an ellipse
- b 2 :
-
exterior fiber width
- b 1 :
-
interior fiber width
- b :
-
=b 2−b 1
- F :
-
stress correction factor
- h :
-
thickness of the beam
- H :
-
\(H = \left( {\frac{{ba_2 }}{h} + b_1 } \right)\)
- I y :
-
moment of inertia abouty-axis
- I z :
-
moment of inertia aboutz-axis
- I yz :
-
product of inertia
- J y :
-
polar moment of inertia abouty-axis
- J z :
-
polar moment of inertia aboutz-axis
- J yz :
-
polar product of inertia
- M y :
-
bending moment abouty-axis
- M z :
-
bending moment aboutz-axis
- R :
-
radius of curvature of the centroidal axis in the unloaded condition
- R 1 :
-
=R 0−a 1
- R 2 :
-
=R 0+a 2
- x z :
-
fiber width parallel toz-axis
- y :
-
fiber distance from centroidal point, along they-axis
- z :
-
distance of point from Ccentroidal point, along thez-axis
- σ E :
-
bending stress, elementary theory
- σ W :
-
bending stress, Winkler's theory
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Raftopoulos, D.D., Qassem, W. Biaxial bending stresses and stress factors in trapezoidal and elliptical cross-sectional curved beams. Acta Mechanica 68, 71–94 (1987). https://doi.org/10.1007/BF01182017
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DOI: https://doi.org/10.1007/BF01182017