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RE: what's wrong - Soil Investigation Requirements

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Man, nice catch.  The picture gets rosier all the time.  "No exceptions -- just do it, love it, and stop whining."
-----Original Message-----
From: Acharya, Suresh [mailto:Suresh.Acharya(--nospam--at)]
Sent: Wednesday, January 16, 2008 9:22 AM
To: 'seaint(--nospam--at)'; 'sgordin(--nospam--at)'
Subject: RE: what's wrong - Soil Investigation Requirements

This article by S.K. Ghosh and Susan Dowty, S.E. summarizes the soil investigation requirements. Regarding the exception of 1802.2: "....What may come as even more of a surprise is that the exception for a soils report found in Section 1802.2, which reads as follows, is not applicable to structures assigned to SDCs D through F..."
"A code user may not initially recognize that the exception does not apply to structures assigned to SDCs D through F. However, upon close reading of the exception, one notices that it only references Sections 1802.2.1 through 1802.2.6, and it is Section 1802.2.7 that requires a soils report for any structure assigned to SDC D, E, or F. This mandatory requirement of the IBC for a soils report for any structure assigned to SDC D, E, or F will result in a major change in California practice where the UBC has not automatically required a soils report based on seismic zone."

Suresh Acharya, S.E.
-----Original Message-----
From: Steve Gordin [mailto:sgordin(--nospam--at)]
Sent: Monday, January 14, 2008 11:10 PM
To: seaint(--nospam--at)
Subject: what's wrong?

2006 IBC and 2007 CBC, Section 1802.2.7 refers literally to "Seismic Design Category D, E, and F" per "Section 1613."
The latter section  refers to SDS A, B, C, and D (of course, no E & F).  However, the Site Class can be designated as A through F.  I guess, the above section should read "Seismic Design Category D."
May be it is just too late, and I am not thinking straight.  If not - was this annoying error somehow corrected? I did not see this in the errata for the printings 1, 2, and 3... 
And why on earth would somebody come up with this extremely confusing idea of two sets of identical designations intended to be repetitively used in the same sections of the code?  I mean, confusing not only to the practicing engineer, but, apparently, to the code writers themselves?
Finally, how are your spreadsheets moving along?  My spreadsheets for the new code are about three times longer than the previous ones.  Because of such length, as well as an extreme amount of weirdly named coefficients, the analysis is hard to follow, and the physical sense of the problem is all but lost.  
IBC made it all but impossible to do calcs by hand.  In the long run, this is not good.
Oh well...
V. Steve Gordin, SE
Irvine CA