When shear stress in a combined footing does not exceed 5 kg/cm2, the nominal stirrup reinforcement provided is________________?
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Answer: B. 8 legged
Explanation
Low shear stresses up to five kg per square centimeter require minimal stirrup density. Engineering practice prescribes eight-legged nominal stirrups for heavy combined footings. This reinforcement level satisfies minimum code requirements for crack control. Shear stress measures internal sliding forces generated across concrete sections. Stirrups are transverse steel bars designed to resist diagonal tension cracks. Combined footings experience significant shear due to high column reactions.
Foundation design must prevent catastrophic shear failures beneath heavy columns. Nominal stirrup provisions ensure ductile behavior even under low shear conditions. Civil construction specifications mandate minimum transverse steel percentages. Option A specifies six legged stirrups which are below standard heavy footing requirements. Option C proposes ten legged stirrups which are reserved for extreme shear forces. Option D suggests twelve legged stirrups which exceed standard nominal detailing needs.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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