What is Bending: Definition and 665 Discussions

In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element.
The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or less, of the other two. When the length is considerably longer than the width and the thickness, the element is called a beam. For example, a closet rod sagging under the weight of clothes on clothes hangers is an example of a beam experiencing bending. On the other hand, a shell is a structure of any geometric form where the length and the width are of the same order of magnitude but the thickness of the structure (known as the 'wall') is considerably smaller. A large diameter, but thin-walled, short tube supported at its ends and loaded laterally is an example of a shell experiencing bending.
In the absence of a qualifier, the term bending is ambiguous because bending can occur locally in all objects. Therefore, to make the usage of the term more precise, engineers refer to a specific object such as; the bending of rods, the bending of beams, the bending of plates, the bending of shells and so on.

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  1. H

    Does an electron beam bending lose energy by photon emission

    A beam of electron in vacuum with velocity v enter a region of spa e with a electric field E. The field is such the electrons circle with radius r. The electrons are now accelerating at constant tangential speed. Because this is not an atomic orbital then by classical physics the electrons...
  2. zaakir

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  3. Jonski

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  4. M

    Stress Comparison for Simply Supported Beams for Engineers

    I have a quick question in relation to the Engineers theory of bending when applied to simply supported beams. I am using the following portion of the theory to determine the stress in a simply supported beam when subjected to bending: Stress = My/I Is it appropriate that I compare the...
  5. S

    Preferential bending loading direction of a beam

    Hi All, I'm trying to think through a problem and was hoping to ping the community for guidance. Suppose you have a beam that's symmetric about 2 axes (like a u channel or a triangular extrusion). Is it better to load the beam in compression on the side with material furthest away or should you...
  6. Aurghyadip Kundu

    Bending of Light in diffraction? Is it actually possible?

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  7. P

    Understanding Bending Moment Diagrams for Multiple Planes

    can someone explain why this problem would involve two bending moment diagrams, one for the xy plane and another for the xz plane? Also, how are the reaction forces at B and C determined each time?
  8. C

    Maximum bending Moment and Maximum Shear Stress Question

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  9. A

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  10. S

    How Do You Calculate Strain Energy in Beams Using Integral Equations?

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  11. P

    How Does a Perpendicular Force Affect a Fixed Elastic Rod?

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  12. D

    Producing a shearing force diagram and bending moment curve

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  13. R

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  14. R

    Accurately Bending Pipes: What Info Do You Need?

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  15. D

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  16. S

    Bending strength of timber and modulus of elasticity.

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  17. R

    Bending and Shear Forces Homework Solutions

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  18. HorseRidingTic

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  19. A

    Bending of beams: calculation of stresses

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  20. P

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  21. J

    Question about the location of max bending stress in a beam

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  22. M

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  23. C

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  24. David Lewis

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  25. R

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  26. M

    Strength of materials/Max bending moment

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  27. H

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  28. shott92

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  29. T

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  30. C

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  31. Daumantas

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  32. C

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  33. P

    Bending space and space time - what is the difference?

    Sorry... This question may be very basic. As a self taught, I understand that the mass will bend the space around it such that any other mass entering the bent space will immediately be pushed towards the center because of the bent space. Higher the mass, higher will be the bent (if that is the...
  34. G

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  35. T

    Bending Space: Unraveling the Mystery

    As I hold a paper back book and bend it, I do not understand this idea of bending space. If I suppose the book and the air around it are really space, when I bend the book, that part of "space" goes into other parts of "space". Further, there must be space where the bending space once ways. What...
  36. SpiderET

    Interpretation of double bending / deflection

    Probably the most famous experiment confirming GR is bending of light by Sun. Here are the best explanations to this topic what I have found: http://www.mathpages.com/rr/s8-09/8-09.htm http://mathpages.com/rr/s6-03/6-03.htm Especially the graph of GR double bending vs Newtonian bending is...
  37. P

    Bending moment and Shear Force

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  38. P

    Bending Tubes with Feet: Efficient Calculation in English Units

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  39. DrVirz

    Where is the point of maximum compressive stress in bi-axial bending?

    Hi all, I've attempted this question however my solution seems too simple..? I have taken the point 'A' (bottom right corner of beam) as the point with max compressive stress, I am not sure if this is correct. I have just assumed this by observation.
  40. S

    Position and magnitude of the maximum bending moment

    Homework Statement I need to calculate the position and magnitude of the maximum bending moment. Knows are: E=210GPa Homework EquationsThe Attempt at a Solution I've calculated the following: R1=33kN R2=32kN From the shear force diagram I know that at 2m from R1 at the concentrated load of...
  41. A

    Bending moments and points of contraflexure

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  42. F

    Bending of tapered (nonsymmetric) beams

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  43. DrVirz

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  44. T

    Explaining Bending Stress in Cantilever Beams

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  45. S

    Light Bending: Why Don't Waves Bend at Normal Incidence?

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  46. spovolny

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  47. S

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    Dear Colleagues, This problem causes me a headache - any suggestions? I have a truncated cone under bending on two axes. I take a section where I have two acting side forces - Qx & Qy I want to find shear stresses acting in the point A which is on a circumstance of the section 45° between axes...
  48. AshUchiha

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  49. A

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  50. H

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