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Shear Walls

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I am designing a building that is seven story high. And here in the
Philippines, we are required to use elevators for 5-storey high structures.
Can anybody out there offer me suggestions? I intend to use the elevator
housing as a shear wall. That is based on my experience.  For a change, I
was thinking of providing an elevator housing but is not connected to the
Lateral Force Resisiting Element.
The structure would act as a special space moment resisting frame rather
than a dual structure. 
Suggestions are most welcome. 
I know that by using a shear wall, there is a need to consider many things
in the seismic analysis.
Thanks in advance guys !!!!!

Allan Yango
Structural Engineer

> ----------
> From: 	Charles Greenlaw[SMTP:cgreenlaw(--nospam--at)speedlink.com]
> Reply To: 	seaint(--nospam--at)seaint.org
> Sent: 	Thursday, March 25, 1999 6:17 PM
> To: 	seaint(--nospam--at)seaint.org
> Subject: 	Re: Residential Flexible/Rigid Diaphragm Analysis
> 
> Responding to Dennis Wish's recent solicitations:
> 
> Dennis, if you are gleaning prior postings for an Online article, I
> submitted quite a bit on the diaphragm rigidity issue in 1998 on Aug 29
> and
> Nov 18 and 21.
> 
> I still think the code's demand that we regard diaphragms as conforming in
> reality to the extremes that human-invented figures of speech suggest
> ("rigid" and "flexible") is the dumbest thing since when young ladies were
> similarly divided into two distinct categories. You remember, there were
> "good girls" and "bad girls". And nothing else. The first kind were good
> for
> marrying and bearing your children. The second kind were good for other
> purposes we need not specify here. 
> 
> Like with this spurious code expectation that we can tell the difference
> in
> diaphragms and rely on the result, telling the difference between good and
> bad girls hasn't been all that certain. My great-grandfather F.B.Ogden in
> Oakland wouldn't let his daughters wear any red clothing, because it was
> "the sign of the fallen woman". His judgment seems quaint now, but the
> voters back then kept re-electing him as a superior court judge.   
> 
> In my own youth, the girls themselves, when it came to being good or bad,
> seemed to sort out behaviorally as "rigid" or "flexible", so to speak.
> Performance-based evaluation, we might proudly call it now.
> 
> But back then, the girl classifications were just for guideline purposes.
> You didn't get sued or lose your license and retirement savings if you
> mistook one kind of girl for the other and made a poor choice. But with
> the
> building code, mistaking rigid for flexible is disastrous as soon as an
> adversary's expert opines you got it wrong. The fact that the building
> itself didn't care is only a curiosity. You are into an expensive defense
> for violating a regulation intended to protect people from injury. Serious
> business.
> 
> So how did this pitfall come to be inflicted on us? I suggest looking to
> Mark Gilligan's posting on 2-27-99, the pertinent part of which is:
> 
> >I have observed that a number of code provisions have been adopted with
> >little technical data backing them up.  The SEAOC Seismology committee
> has
> >generally done a good job but ultimately the individuals find themselves
> >having to make decisions on subjects that they have not seriously
> >researched.  In this context people use their  best judgement.  I believe
> >that the provisions on redundancy probably fell in this catagory. The
> >problem is that what may seem rational occasionally isn't.
> 
> I discussed Mark's implication in early March at a SEAOC dinner meeting
> with
> another regular code formulation participant, who is with a state agency
> keenly concerned with seismic codes. He confirmed that code language very
> often comes from one person on a committee, usually an energetic and
> forceful advocate, and gets approved with little or no validation in
> depth.
> Usually voting committee members shoot from the hip on little
> knowledgeable
> debate, because the agenda is too full, and was distributed too close to
> the
> meeting date to absorb and find flaws in. And the plane home leaves too
> soon. This is what my own experiences confirm. On the few issues I can get
> up to speed on and find big defects in, it is still hard at the meeting to
> get an edge in wordwise. I have in past writings referred to these
> committees as "empires" and been told that is an understatement.
> 
> I do better at Board of Registration meetings. I have spoken on
> enforcement
> issues and pointed out an anomaly:   The Board disciplines individual
> engineers for failure to fulfill the duty of due care, such as mistakenly
> making a code violation, on a single element of a single building. But the
> code provision itself was originated with less care than taken by the
> offending engineer in its use. And the code doesn't just affect that one
> building, it affects all buidings. With less care taken. How do you Board
> of
> Registration members want to discipline that??  Blank stares follow; no
> complaints were received so they have no idea. But why should the
> struggling
> code users suffer the burdens? Why not the code originators? The stories
> of
> code formulation proceedings are plainly stories of failure to render due
> care. 
> 
> Questioning "authority" itself, not the orders disseminated by authority,
> is
> where this subject's inquiry should head.
> 
> Charles O. Greenlaw, SE    Sacramento CA
> Vietnam Vet who hasn't forgotten what can happen
> 
> 
> 
>