In practical design of steel structures, on the vertical walls, external pressure coefficient on windward wall is
- A0·8Correct
- B0·5
- C– 0·5
- D– 0·8
Solution
Concept
External pressure coefficient (IS 875 Part 3)
Step-by-step solution
1. The windward face of a vertical wall receives positive pressure. 2. The usual design value of the external pressure coefficient is +0.8, while the leeward wall is taken as suction (−0.5).
Explanation
Windward walls are pushed by the wind (positive coefficient), so the answer must be positive; the practical design value is 0.8.
Why the other options are wrong
Negative coefficients indicate suction (leeward walls or side walls), and 0.5 is smaller than the usual windward value.
Shortcut
Windward +0.8; leeward −0.5.
Common mistake
Taking −0.5 (leeward).
Correct answer: A) 0·8