ASCE 7-10 Tank Wind Loading - Fig. 29.5-1: D/SQRT(qz)? OR D*SQRT(qz)?

[pettus71]

All,

I am trying to get the wind loading for a tank. In ASCE 7 (past and present) it appears in Figure 29.5-1 that the designer is to multiply D*√q_z. However, in a reference webinar I was looking through he divided D/√q_z. I have attached a screenshot of the webinar example. So should I divide or multiply? Dividing makes more sense to me, but I have also found other sources that appear to multiply. I have looked through the last several versions of ASCE 7 and they all have the same figure.

Thanks in advance!

 

[IFRs]

Are you designing or checking an API or AWWA tank? If so, you may want to check those codes.