From: "Ron O. Hamburger" <ROH(--nospam--at)eqe.com>
Date: Tue, 4 Jan 2000 07:10:30 -0800
On 1/3/2000, Ken Wilkinson wrote:
"Tim McCormick the Building Official at the City of Santa Monica wants a
Rigidity Analysis (1630.6) and a Story Drift Analysis (1630.10) for a one story
residence no matter what Seaoc or LA City says. I used the Simplified Design
Base Shear Method. A lot of Mr. McCormick's information comes from a SEAOC
Seminar, Wood Diaphragms and Shear Wall Defections,.authored by Douglas Thompson
S.E. in which is stated "Past earthquakes have shown that lateral forces are
distributed by relative rigidities."
I would appreciate any help and how to handle this situation?
Ken Wilkinson S.E.
The Simplified Method of Sectoin 1630.2 is specifically intended to permit
relaxed approaches to design, and in particular exempts story drift checks from
the applicable provisions. You may wish to get a formal ruling from ICBO in
Whittier, California as to how this section is to be interpretted and wether
rigid diaphragm analysis is required. However, in the end, the building
official is the last word on what is acceptable in a given situtation (he is
called the Authority having Jursidiction) and what is not. Most City's have an
appeals procedure in place, in which you can try to have the building official's
ruling overturned. It is a difficult and time consuming (expensive) process.
The simplest path forward may just be to do what the building official requests,
which is to perform the requested analysis.