ASCE 7-05 Wind

[OCI]

I'm trying to get a better grip on the ASCE 7-05 wind loads. Within method 2 there are 2 versions. One is for buildings < 60' and one is for "All Heights". Is the intent that the user has the option to choose between the 2 for buildings < 60'? Or is it inappropriate to use "All Heights" for < 60'? The reason I ask is because the < 60' option appears to be more complex to implement in a spreadsheet due to the corner zones. And also limited by height. My second qustion is in regard to these corner zones. Are they to be used at every corner of a building or just the corners at the edge of the envelope? Thanks.

 

[WillisV]

All heights method can be used for buildings <60'.

Corner zones are a subject of some engineering judgment and are not really discussed in the code. The intent is for them to represent discontinuities in the airflow. SEAW/ATC60 provides some guidance - they indicate that inside (reentrant) corners as well as exterior corners with an included angle of >170 degrees (i.e. very shallow corners) do not qualify as discontinuities and are therefore not corner zones.

 

[OCI]

Thanks for the reply.