Rounded corner wind load
Rounded corner wind load
(OP)
Hi guys,
I am tying to work out the wind load for a 100 meter tall building by using AS1170.2. The building has no shape edges(corner radius very large compare to the building's width and length), Just wondering should I apply Kl=3 to the side wall negative wind load in this case? If yes, is there a corner shape modification factors for me to take into consideration within the AS?
thanks
I am tying to work out the wind load for a 100 meter tall building by using AS1170.2. The building has no shape edges(corner radius very large compare to the building's width and length), Just wondering should I apply Kl=3 to the side wall negative wind load in this case? If yes, is there a corner shape modification factors for me to take into consideration within the AS?
thanks






RE: Rounded corner wind load
In the absence of such a study I would not use Kl=3 as I feel this is too conservative given you should not expect high suctions to develop on a rounded corner. Section C5.2.1 does not specify any local factors for circular tanks, which is a similar situation to yours.
RE: Rounded corner wind load
According to your recommendation, if there is a rounded shape building, its wind load should be carried out by the section C5.2.1, circular bins then. Am I correct?
RE: Rounded corner wind load
Are you looking at the global stability of the building? Or just a small area of cladding?
RE: Rounded corner wind load
I believe that you are correct Trenno. I assumed that hi5chenchen was looking at the cladding design.
RE: Rounded corner wind load
thanks
RE: Rounded corner wind load
C5.2.1 is for a circular tank. Table 5.6 is for a rectangular building. You are not really either of these situations - you are somewhere in between. Therefore you are going to have to use engineering judgement to come up with a solution. I'm sure different engineers will come up with different solutions. If you don't get a satisfactory answer here I would phone up some local wind engineers and try to pick their brains.
RE: Rounded corner wind load
RE: Rounded corner wind load
If you are able to give me some tips from other professionals, I'd be much appreciated.
RE: Rounded corner wind load
RE: Rounded corner wind load
Google is also your friend... Relevant discussion
Also why don't you download the Autodesk Robot Free Trial and give the wind simulation a whirl (yes, pun intended). Test pressures on a rectangular Vs cylindrical model.
RE: Rounded corner wind load
EVERY building which has cladding (windows or panels) that have failed has required months - sometimes years! - of very, very expensive repair and re-design efforts and trials-and-errors rework. Ugly, failed solutions in every case. ALL of them required tens of millions, sometimes hundreds of millions, of repairs that taint the building, the designer (the company and architects) years later.
So, you have started with a "lesser problem" than some cases: slightly rounded corners and a sligthly more modest height than a few problem cases. That will push you towards lower failure rates, but you are not out of the envelope yet since the prying and vibrating forces are "local" and may happen anyway as winds get exaggerated by swirls and flows from nearby buildings and nearby plazas and open spots.
With that risk, without a specific wind analysis, I'd use the rounded edges only to buy the greater safety margin from failure, and "sell" it to the project team that way, rather than to try to justify a theoretically smaller (and thus slightly cheaper) joint and tie-back and connection system. Greater reliability.