Wind loads are randomly applied to dynamic loads. The intensity of the wind pressure on the surface of a structure depends on wind velocity, air density, the orientation of the structure, the area of contact surfaces and the shape of the structure.
The terrain is used to refer to an area of land or type of land when you are considering it is a physical feature.
Category 1- Exposed open terrain with few or no obstructions and in which the average height of any object surrounding the structure is less than 1.5m
Category 2-Open terrain with well-scattered obstructions having heights generally between 1.5m to 10.
Category 3-Terrain with numerous closely spaced obstructions having the size of building structure up to 10m in heights with or without a few isolated tall structures.
Category 4-Terrain with numerous large high closely space obstructions.
CLASS A-Structures and/or their components such as cladding, glazing, roofing etc having a maximum dimension or less than 20m.
CLASS B-Structures and/or their components such as cladding, glazing, roofing etc.having maximum dimension between 20m and 50m
CLASS C-Structures and/or their components such as cladding, glazing, roofing, etc.having max. dimension greater than 50m.
RULE OF WIND LOAD APPLY
Building story up to 4 to 5 less is not applied wind load.