Question

Where does the maximum bending stress occur in a simply supported beam?

• A. At supports
• B. At mid-span
• C. At quarter span
• D. At free end

Hint:

Remember: Max bending stress → where bending moment is maximum (mid-span).

Answer 1

The Correct Option is B

Concept: Bending stress in a beam depends on the bending moment, which varies along the length of the beam.
Step 1: Relation of stress and bending moment.
\[ \sigma \propto M \] Maximum bending stress occurs where bending moment is maximum.
Step 2: Simply supported beam behavior.
For a simply supported beam with uniform load, the bending moment is maximum at the center (mid-span).
Step 3: Evaluating the options.

• At supports $\rightarrow$ Bending moment is zero (incorrect)
• At mid-span $\rightarrow$ Maximum bending moment (correct)
• At quarter span $\rightarrow$ Not maximum (incorrect)
• At free end $\rightarrow$ Not applicable (incorrect)

Step 4: Conclusion.
Thus, maximum bending stress occurs at the mid-span.