ASCE 7 Wind

[ddcpe]

Can anyone point me to where in ASCE 7 the "Load Case" in the third column in Figure 6-2 is specified? In the accompanying diagram (figure 6-2) they mention load case 2 in note 4 but I can find no place in the text of ASCE 7, Chapter 6 where Load Case 1 & 2 are directly specified in writing.

 

[msquared48]

Apparently, you are looking at Method 1, and I cannot find anything directly relating either.

However, if you turn to Figure 6-9, there are four load cases there. This may be an entwinement of the two Methods, inadvertent or otherwise, that, admittedly, should be clarified better in Figure 6.2.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[JedClampett]

In looking at the tables, load case 2 only enters when the roof angles are more than 25 degrees. So it looks like the additional load case that must be considered for highly sloped roofs. It appears to be one of those quirks that we love so much in ASCE 7, chapter 6.
In ASCE 7-10, it says that "Where two load cases are shown, both load cases must be investigated. Load Case 2 is required to investigate maximum overturning on the building from the roof pressures shown."

 

[ddcpe]

Thanks guys. As I have always supposed the two cases are as illustrated but not labeled in figure 6-2. An irony here is that I have called and sent emails to ASCE to get clarification here and nary a reply.