Friday, September 30, 2011

Re: Wind forces on the columns of open structure


For the roof I would use the Wind Force Coefficients from ASCE 7-05 Figure 6-18A and for the columns I would use the values from Figure 6-21 and put the load on the full length of each column.  If the wind load comes in with only a slight angel to normal all the columns will see the full unobstructed load.

Thomas Hunt, S.E.

From:        Joseph Grill <>
Date:        09/30/2011 10:13 AM
Subject:        Wind forces on the columns of open structure

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?

Joseph R. Grill, PE

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