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Bending stresses in a rectangular beam under transverse loading When a rectangular beam is transversely loaded producing sagging (positive) bending moments, where is the maximum compressive stress developed? Choose the correct location.

Difficulty: Easy

top layer
bottom layer
neutral axis
every cross-section equally

Correct Answer: top layer

Explanation:

Concept
For sagging (positive) bending moments in a prismatic beam, the top fibers are in compression and the bottom fibers in tension; stress varies linearly from maximum compression at the extreme top to maximum tension at the extreme bottom.

Therefore
The maximum compressive stress occurs at the top layer.

Final Answer
top layer

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