Given a simply supported slab maximum bending moment of M kg.cm, express its effective depth (where Q is the moment of resistance factor)________________?
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Answer: D. (M/100Q)
Explanation
The effective depth of a simply supported slab is determined using the square root relation of the maximum bending moment divided by factor Q. Flexural resistance formulas equate the resisting moment of the concrete section to the applied maximum bending moment. Rearranging the standard moment of resistance equation yields the required effective depth enclosed within the square root expression. Effective depth is the perpendicular distance from the extreme compression fiber to the centroid of tensile reinforcement. The moment of resistance factor Q incorporates material allowable stresses for concrete and steel in working stress design. Square root relationships arise naturally from flexural equations where section depth scales with the square root of the bending moment.
Option A introduces an incorrect scaling divisor and lacks the necessary square root operation for depth calculation. Option B omits the square root function, resulting in dimensionally inconsistent and structurally unsafe depth values. Option C has incomplete bracket formatting and fails to correctly represent the mathematical depth formula structure.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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