For structural carbon steel under static loads, the allowable working stress is normally assumed to be__________________?
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Answer: C. 4000-4500 kg/cm2
Explanation
Structural carbon steel possesses well-established mechanical properties defined by national engineering standards. Under static loading conditions, safe allowable working stress limits are established using standard factor of safety margins. For structural carbon steel, this safe allowable working stress is typically set around 4000 to 4500 kg/cm2. Allowable working stress represents the maximum safe stress level permitted in a structural member during service. Yield strength and ultimate tensile strength serve as the baseline mechanical properties for determining working limits. Static loads remain constant or change gradually without introducing dynamic shock or fatigue considerations.
Ranges like 2000 to 3000 kg/cm2 are overly conservative and underestimate the true static load capacity of carbon steel. Values between 3000 and 4000 kg/cm2 fall slightly below standard allowable working stress limits for structural carbon steel. Values above 7500 kg/cm2 exceed the ultimate yield strength of standard structural carbon steels, causing failure.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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