Friday, September 30, 2011

Re: Wind forces on the columns of open structure

Neil,
Coastal exposure D, so the kite thing is definitely on our minds. Just looking for a little direction on the loads to the columns. I don't see in ASCE where it is addressed, therefore my comment about section 6.5.15.
Thanks, Joe

On Sep 30, 2011 2:01 PM, "nma" <nma@nma-se.com> wrote:
> Joe:
>
> How big are the columns? I would load up all the columns and ignore any
> shielding effects. One of the things I've seen in this kind of a
> structure is vibration - i.e. small shaking of the whole thing. It may
> also makes a small difference in the shape of the columns - round or
> rectangular? You didn't say what the wind speed or exposure factor is
> or where the structure is located - i.e. on a hill or in the middle of a
> city.
>
> For the flying bit - I've have been criticized for larger footings than
> the city inspector thinks the footings should be. But I signed for the
> structure and not him. I've also seen the result of a roof flying off
> its supports - had my back turned with it happened.
>
> Neil
>
>
> On 9/30/2011 10:47 AM, Joseph Grill wrote:
>>
>> Neil,
>> Thanks, I understand the flying bit. But there is going to be a
>> lateral wind load on the columns themselves. I am looking for the
>> criteria to determine the horizontal load to the columns.
>>
>> On Sep 30, 2011 1:38 PM, "nma" <nma@nma-se.com
>> <mailto:nma@nma-se.com>> wrote:
>> > Joe:
>> >
>> > Just figure it is going to try to fly.
>> >
>> > Neil
>> >
>> >
>> > On 9/30/2011 10:16 AM, Joseph Grill wrote:
>> >>
>> >> I tried to send a message yesterday on this subject. But with new
>> >> phones, new wireless providers, a move across country etc i'm not sure
>> >> it went through.
>> >>
>> >> Anyway I am designing an outdoor picnic pavilion. The plan dimensions
>> >> are about 60' x 30'. It will have monoslope roof supported by 4 bays
>> >> of 3 columns. I have calculated the wind loads for the MWFRS at the
>> >> roof. I can't decide on what ASCE requirements/equations to use for
>> >> the MWFRS loads to the columns and if that load should be applied to
>> >> each column in each row parallel to the load direction. In another
>> >> words if there are 4 columns in line parallel to the wind load would
>> >> all 4 columns be loaded?
>> >>
>> >> I have considered using loads calculated from section 6.5.15 "Design
>> >> Wind Loads on Other Structures". Am I wrong? If so can anyone suggest
>> >> what i should be doing?
>> >>
>> >> Thanks,
>> >> Joseph R. Grill, PE
>> >>
>> >
>> >
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