Fixed End Moment - Clockwise or Anticlockwise?

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The discussion centers on the confusion regarding the fixed end moments of a beam, with conflicting information from a textbook and Wikipedia. The textbook states that the fixed end moment is clockwise on the left span and anticlockwise on the right, while Wikipedia claims the opposite. Both sources assign clockwise moments as positive, leading to discrepancies in bending moment diagrams. Clarification suggests that the textbook refers to the moment due to beam loading, while Wikipedia discusses the wall's reaction moment. Ultimately, the fixed end moment is understood as the reaction moment opposing the beam's loading.
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Homework Statement



In the book (photo 1 ) , it's stated at the left span, the fixed end moment is clockwise , while on the right span , the fixed end moment is anticlockwise . But , accroding to wiki (photo2) , it's stated that at the left span of the beam , the fixed end moment is anticlockwise , while on the right span , it's clockwise ...

In both cases , clockwise moment is assigned as positive . Which case is correct ? I'm confused . ht//en.wikipedia.org/wiki/Fixed_end_moment

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The Attempt at a Solution



IMO , only one of it an be correct . This is because as the In both cases , clockwise moment is assigned as positive . When we drawing the bending moment diagram , it will lead to different answer . [/B]
 

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It looks like the book is talking about the equivalent moment of the beam loading (note the circular arrow is on the beam side). The Wikipedia article appears to be referring to the wall's reaction moment to the beam loading. Note that you should expect these two moments to be equal magnitude and opposite direction, since the beam has not been caused to spin.
Similarly, when you are standing on the ground, often we talk about your weight as a force pushing down on the ground. But there is also the equal force of the ground pushing up on you, keeping you from falling into the ground.
 
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scottdave said:
The Wikipedia article appears to be referring to the wall's reaction moment to the beam loading. Note that you should expect these two moments to be equal magnitude and opposite direction, since the beam has not been caused to spin.
So , fixed end moment is the reaction moment ?
 
fonseh said:
So , fixed end moment is the reaction moment ?

That is what it looks to me, in the Wikipedia article is referring to, the way they drew the arrows.
 

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