Wind load - Internal and external pressure coefficients

This video explains how to determine pressure coefficients for the design of buildings for wind loads. Internal and external pressures are considered, although with various clauses in SANS 10160-3.
Also visit our other TH-cam channel, FireSUN, for more videos.
Produced for the SD424 Structural Design course.
Copyright Stellenbosch University.

[@darshanmadhav5807]

One of the best videos explaining wind loads and pressures for a student doing a design course... Keep up the great work!!!

[@richard_walls]

Glad you enjoyed it.

[@haider254]

Thanks a bunch! This pretty much matches up with the Eurocode procedures as well.

[@giulianagrasso5445]

Thank you so much for the explanation! Everything is so clear!

[@dveloso150]

I'm trying to design a 300 sq ft building and wanted to know the structural components for 250mph, 300mph and 350 mph wind loads. Is this something difficult to do or is there a software that can easily adjust the components to support the different loads?Thank you

[@richard_walls]

You will need a structural design for that based on the geometry of the building. There are no quick tables for such member sizing. Also those wind speeds are insane.

[@YONAHIMEGAMING]

Thank you very much. It was very informative and helpful.

[@structurex-zx4yk]

Great explanation and best visual aid i saw...

[@silvymallous7042]

Wowwww🤩 so clear explaining thank you so much

[@ahmedelteheiwey2536]

Very useful and clear video. You're the best!

[@omarjamoussi6388]

Is this video using eurocode 1 ? If yes what about an asymmetrical roof ?

[@richard_walls]

@@omarjamoussi6388 it uses SANS 10160. However, for a mono symmetric roof there are good guidelines in both codes. For a asymmetric roof you will need engineering judgement or a CFD analysis or wind tunnel test

[@klutzy1]

Thanks alot for the video. Very informative

[@junweili357]

Great presentation, Richard. I have a question what will change if we design an unroofed building?

[@richard_walls]

If you have no roof then you just have walls. You will design that based on wall pressured coefficients most probably, depending on the arrangement of the walls.

[@anshadzaman2725]

Thank you for the video. Well explained.

[@kennyomega8937]

Thank you so much. I like the way you explain

[@tokiniainaricky8588]

Thank you so much, this is the best explanation by far I have seen on youtube

[@mudimbipierrot6348]

Thanks very much for the knowledge! your efforts are really appreciated.

[@matthewjones8402]

Thanks for the video. If you were to consider a case where doors are all shut. Do you assume all internal pressure coefficients to be 0?

[@ahmadzamanifar4987]

100 OF 100

[@madikgolephalane1808]

Great video, what if there are no walls on all the sides of the building? Just the roof, more like a carport design?

[@sampsonagudze8674]

Fantastic tutorials! Thanks

[@TheEngineeringProf]

On behalf of all UJ 3rd Year BEng Civil Eng students, thank you!

[@richard_walls]

Thanks Prof. Glad it is useful to them.

[@33cmane]

Superb method of Explanation... thank you so much

[@melisazimwara4879]

Hello, Prof I don't know if that might be a stupid question. From what you have explained we have considered the doors on the dominant wall open, how would we design if the doors are closed? Will the pressure just be the external pressure then? Don't know if my question is quite clear.

[@richard_walls]

Dear Melisa. When the doors are closed they are ignored and the internal pressures treated with either (a) calculating cpi based on the windows that are open (if you know where they are, or (b) taking cpi as the more onerous (worst case) or +0.2 and -0.3. The latter is a simple approach when there are various small openings and no specific dominant areas. In complicated buildings this often applies.

[@bbetchine58]

Hello, what is the internal pressure coefficient for a frame without a wall, thank you

[@venkatesh2285]

How to calculate wind pressure downward and uplift open carport structure like cantilever

[@richard_walls]

Each wind loading code has a section on canopy roofs. They provide pressure coefficients to suit. The pressure is a function of the blocking factor. You also need to apply the load eccentrically in some cases to account for uneven pressure distributions.

[@georgen9755]

Master peaceless
Dots

[@johnbriggs7514]

Awesome thanks so much.

[@denorshabuchanan-willock5592]

What if no dominant opening will occur during periods of high
wind?

[@richard_walls]

Guidance is provided in the code. For example, for a airplane hangar where the doors will be closed during storms that may not be considered at ULS. However, it should then be considered as an accidental case because it could happen, but some damage may be permitted.

[@denorshabuchanan-willock5592]

I have be looking through the code however i am unsure if i need to use the figure Figure 7.13 Table or that cpi
can be taken as the more onerous of +0.2 and -0.3. Because in my case with a portal frame, i am assuming that our structure has no dominant opening. What would be best ?
@@richard_walls

[@denorshabuchanan-willock5592]

Also, Thank you for responding so promptly, i appreciate it.

[@AnupBiswaschin2ji]

Superb

[@jasonRhawt]

How does the internal pressure behave when there are no opening inside? i'm assuming internal pressure will cause a constant suction inside when wind is applied externally.

[@richard_walls]

There are always done small openings around a structure. Simplified guidelines of -0.3 or +0.2 cover such a case to approximate details when you're not quite sure what the internal pressure is.