Cantilever, pin and UDL confusion

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Discussion Overview

The discussion revolves around the analysis of a cantilever beam with a pin support and a uniformly distributed load (UDL). Participants explore the implications of the beam's configuration on the bending moment diagram (BMD) and shear force diagram, addressing confusion regarding the load distribution and support reactions.

Discussion Character

  • Technical explanation, Debate/contested

Main Points Raised

  • One participant describes a 10 metre cantilever with a pin in the middle and a roller at the end, expressing confusion about the bending moment diagram and shear force diagram.
  • The same participant calculates a 50 kN load at the fixed end and roller but questions the implications for the BMD being zero at the pin.
  • Another participant seeks clarification on whether the structure consists of one cantilever or two, indicating potential misunderstanding of the setup.
  • A different participant suggests that the beam is fixed at one end and connected to another beam via a pin, which is roller supported at the other end, proposing an alternative interpretation of the configuration.
  • One participant references the original question, confirming it describes a propped cantilever beam with a pin experiencing a UDL.
  • A later reply indicates that the initial participant resolved their confusion independently.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the interpretation of the beam's configuration, with multiple competing views presented regarding the setup and load distribution.

Contextual Notes

There are unresolved assumptions about the beam's configuration and the implications for the bending moment and shear force diagrams, which may affect the analysis.

dan38
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So I have a 10 metre cantilever with a pin in the middle
There is a roller at the end and a UDL of 10 kN / m acting across.
Drawing the BMD is confusing me.

By my calculations; there should be a 50 kN load acting at the fixed end and roller.
Hence shape of the shear force diagram would be up, negative gradient and then up again.
But this would make it impossible for the BMD to equal zero at the pin.

Moreover when I split the cantilever at the pin, I find that the support reactions equal 25 kN now...

Where am I going wrong?
 
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So I have a 10 metre cantilever with a pin in the middle

??

One cantilever or two or what?
 
one cantilever
 
I think you mean that the beam is fixed at one end, then there is a pin at 5 m which connects another 5 m long beam that is roller supported at its other end?
 
Question says: A propped cantilever beam ABC with a pin at B experiences a UDL of 10 kN/m.
 
dont worry figured it out :D
 

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