Which one of the following is NOT an effect of wind on a structure ?
- AThe effect of wind on a structure depends upon the density and velocity of the air
- BIt depends upon the angle of incidence of the wind
- CIt depends upon the shape and stiffness of the structureCorrect
- DIt depends upon the smoothness of the structure surface
Solution
Concept
Factors on which wind effects depend
Step-by-step solution
1. Wind effects depend on air density and velocity (a), the angle of incidence (b), the shape and dimensions of the structure and the surface roughness (d). 2. "Stiffness" is not in the basic list of factors for static wind pressure (c).
Explanation
The standard list for wind load is: velocity and density of air, angle of incidence, shape and size of the structure, and surface texture. Stiffness is relevant only to the dynamic response.
Why the other options are wrong
(a), (b) and (d) are listed factors.
Shortcut
Wind load factors: velocity, density, incidence, shape, surface.
Correct answer: C) It depends upon the shape and stiffness of the structure