What is a wind load over structure?/What is a wind load in civil engineering?

 Let us go through some of the queries related to wind load in civil engineering as follows.

1. What is a wind load over the building?

The resulting force acting over the structure due to the pressure exerted by the blowing wind is said to be wind load.

The extent of wind load depends upon the exposed surface area of the building, wind speed, & direction of the blowing wind.

2. What are the different types of forces that are exerted by the wind?

The wind creates many types of forces such as twisting, shear, bending, uplift, etc. depending upon the wind direction & geometry of the structure. Mainly, they are categorized as

a. Uplift load:

Wind flow will create a lifting effect over the roof of the structure. 

Wind flowing upward from the bottom of the roof exerts a pushing effect over the roof. In the same manner, wind flow above the roof creates a pulling effect over the roof surface due to the suction pressure.

b. Shear load:

Horizontal wind pressure over the building surface creates the tilting of the structure. The wall & structural members may get cracked or deformed due to the shear load of the wind.

c. Lateral load:

The horizontal wind pressure in an angular direction could make the structure overturn or slide from its foundation.

3. At what height we should consider the wind load?

As per is 875 part-3, (2015) table-2, the wind load should be considered if the height of the structure is above 10m. (33'). 

Generally, the height of one floor will be 3.1m. So, if the building is above 3 storeys, the wind load calculation is required.

Even in NBC of India 2005, it is said that wind load will be applicable for a building above 10m. in height. As per the code, the wind load calculation is a must for all the tall buildings which are above 15m. in height.

4. What are the factors that affect wind load calculation?

The several factors that are considered while calculating the wind loads over the building are,

1. Ground surface & building location.

2. Topography & elevation of the area.

3. Height of the building.

4. Geometry of the building.

5. Surface area & aspect ratio of the building:

6. Wind speed or velocity.

7. Wind direction.

8. Solidity ratio or building openings.

For more such explanatory articles, click here.

Thank you for going through this article❤. Have a good day 😄.

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