0.37 fy
0.57 fy
0.67 fy
0.87 fy
Answer is Right!
Answer is Wrong!
The correct answer is: C. 0.67 fy
The design yield stress of steel according to IS: 456-1978 is 0.67 fy, where fy is the characteristic yield strength of steel. This means that the design yield stress is 67% of the characteristic yield strength. This is done to account for the variability in the strength of steel.
The characteristic yield strength is the minimum yield strength that is guaranteed by the manufacturer. The design yield stress is used in the design of structures to ensure that they are safe.
The following are the options of the question and their brief explanations:
- Option A: 0.37 fy. This is the value of the design yield stress for mild steel. However, the question is asking for the value of the design yield stress for steel according to IS: 456-1978.
- Option B: 0.57 fy. This is the value of the design yield stress for high-strength steel. However, the question is asking for the value of the design yield stress for steel according to IS: 456-1978.
- Option C: 0.67 fy. This is the correct answer. The design yield stress of steel according to IS: 456-1978 is 0.67 fy.
- Option D: 0.87 fy. This is the value of the design yield stress for structural steel. However, the question is asking for the value of the design yield stress for steel according to IS: 456-1978.