Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: 1994 UBC vs 1997 UBC Masonry Design

[Subject Prev][Subject Next][Thread Prev][Thread Next]
The expert on such machiavellian masonry manipulations is Max Porter -
Iowa State.

I am forwarding your dilemna to Max.

jgk



---Edwin Schmeckpeper <eds(--nospam--at)uidaho.edu> wrote:
>
> From a quasi-lurker.
> 
> 
> I have a question about the differences between the 1994 UBC and
1997 UBC
> Strength Design of Masonry provisions.
> 
> 
> It seems as if the 1997 UBC has reduced the load factors for
Masonry, but
> kept the same strength reduction (phi) factors.
> 
> 
> In 1994:  Section 2108 used the ACI load factors 
> U = 1.4D + 1.7L, etc.  
> 
> The phi factors for beams, piers, and columns (for example) were
listed as:
> 
> shear 		phi = 0.6, 
> flexure 	phi = 0.8 - Pu/(Ae f'm)   0.6 <= phi <=0.8
> 
> 
> In 1997: Section 2108.1.3, Says use the factored load combinations of
> Section 1612.2, which are the ASCE-7 load factors.  
> 
> U = 1.2D + 1.6L, etc,
> 
> However, it seems as if the phi factors have not changed.  For
example,
>    
> 2108.1.4.1.1 still says for beams, piers, and columns:
> shear 		phi = 0.6, 
> flexure 	phi = 0.8 - Pu/(Ae f'm)   0.6 <= phi <=0.8
> 
> 
> Is this correct ?   The loads factors have decreased, but the strength
> reduction (phi) factors have stayed the same ?
> 
> In ACI 318-95, there is one set of phi factors to use with the
> "traditional" ACI factors (1.4D+1.7L), and a different, lower set of
phi
> factors to use with the ASCE factors (1.2D+1.6L).
> 
> Am I missing something ?
> 
> 
> 
> Thanks,
> Ed.S.
> 
>
--------------------------------------------------------------------------
> Edwin R. Schmeckpeper, P.E., Ph.D.
> Department of Civil Engineering                   Phone  : (208)
885-6702 
> University of Idaho                               FAX    : (208)
885-6608
> Moscow, Idaho 83844-1022                          E-Mail :
eds(--nospam--at)uidaho.edu
>
--------------------------------------------------------------------------
> 
> 
> 
> 
> 
> 

==
James Korff, PE, PMP, SEAONC 
985 E. Hillsdale Blvd, Suite 128, Foster City, CA 94404
Phone/Fax 650-345-1355
Cellular/Voice Mail/Messages 650-796-8997 
Cyber-Mail: jameskorff(--nospam--at)aol.com  jgkorff(--nospam--at)yahoo.com

"May the DISPLACEMENT be With You !!"
_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com