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RE: ACI 530 R=1.5

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Look at ACI 530 it limits the R to 1.5, but only in the strength section.  City of LA code references 530 to answer the other section.
I saw, and thought thats what they were origianlly referring to, but is pretty clear. But nothing in ASD

--- On Thu, 2/5/09, Paul Feather <PFeather(--nospam--at)> wrote:
From: Paul Feather <PFeather(--nospam--at)>
Subject: RE: ACI 530 R=1.5
To: seaint(--nospam--at)
Date: Thursday, February 5, 2009, 8:35 AM

ACI 530 does not set or establish R factors.  There are only two possible explanations that I am aware of: first if using strength design there is a provision for maximum area of flexural tensile reinforcement ( where M/Vd greater or less than 1 and IF the design used an R of less than or greater than 1.5 is a trigger for additional design requirements.  This is not an R factor limitation, just a trigger for other provisions.  Second would be if they are somehow mis-interpreting the shear force required of 1.5V in ASD design, but this is an IBC requirement and not in ACI 530 either.
I would ask the Plan reviewer to specify which code provision he / she is referencing with his comment.
Paul Feather PE, SE

From: Rick [mailto:mohr2circle(--nospam--at)]
Sent: Thursday, February 05, 2009 7:58 AM
To: seaint(--nospam--at)
Subject: RE: ACI 530 R=1.5

I have a City of LA Plan check comemnt that R = 1.5 "must" be used for masonry walls piers per ACI  530.
Can someone point me to the specific reference.