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Institution Forums > General > Pure bending View modes: 
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Site User - 02/02/2019 07:11:30
Pure bending
What is pure bending ?

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Abhijeet Oundhakar - 03/02/2019 07:37:01
RE:Pure bending
Bending in the absence of shear is called "pure" bending.

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Site User - 04/02/2019 11:46:00
RE:Pure bending

Now for Pure Bending. A couple of notes first:

  1. Bending never occurs without shear, they are just intertwined.
  2. Most structures will be experiencing a combination of the 3 forces at once.

Pure bending is simple when an element is experiencing bending ONLY (with it's associated shear) without any of the other 2 forces. The reason I'm excluding shear here is that bending causes internal shear forces by default, but in pure bending, there is no external force causing shear of it's own.

So breaking a pencil by twisting both ends upwards is pure bending, but breaking it by supporting it over 2 books and pressing down the middle induces shear, thus, NOT pure bending. 

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