13 increase for seismicwind for masonry

huangyhg

1/3 increase for seismic/wind for masonry?
there has been some talk that the 1/3 increase for masonry is going away in the ibc 2006.   but it's still in the ibc 2003, right?  2.1.2.3 of the aci 530-02/asce 5-02 seems to allow the 1/3 stress increase, which can be used with the alternative basic load combinations of the ibc 2003.
what do you think?
look in ibc chapter 21 and make sure that section of aci 530 is permitted.
that's my understanding as well.
haynewp,
your response is bit vague, not too helpful in it's current form.  perhaps you could be more specific if there a particular passage you are aware of?

thanks,
mike
i am away from the office today so i don't have the ibc with me right now, but i know it removes parts of other standards as being applicable (such as aci 530). i don't know specifically if it does this with the 1/3 increase as you stated is in 530, because i don't have chapter 21 memorized. but i would check ch 21 to make sure there is not something like "aci 530 applies with exception of sections 2.1.2.....etc." before i assume the 1/3 increase is permitted by ibc 2003 for masonry.
the 1/3 overstress allowance has been removed from almost every other structural consideration as well....why not masonry now!
in the current ibc, the 1/3 increase is allowed for the alternative load combinations, but that is because the alternative load combinations multiply wind load by 1.3 (which is approximately a 1/3 increase).  i don't use the alternative load combinations, and i don't use the 1/3 increase for masonry (or steel).
daveatkins
i haven't used ibc 2003 as much as 2000. is the seismic force the same between the standard and alternate load combinations or is there some other hidden multiplier as well? i never use the 1/3 increase either anymore, even when i am allowed.
mendacity is a system that we live in. liquor is one way out and death's the other.
-tennessee williams
2101.2.3  prestressed masonry shall be designed in accordance with chapters 1 and 4 of aci-530.
2101.2.4 masonry designed by the empirical designed method shall comply with the provisions of 2106 and 2109 or chapter 5 of aci-530.
2101.1,2  masonry shall comply with 2106,07 & 08
2106.1  masonry structures shall comply with 1.13.2.2 of aci-530.
2107.1 masonry wsd shall comply with chapters 1&2 of aci-530.
2108.1 design of masonry per strength design shall comply with chapters 1 & 3 of aci-530.
there are some exceptions mixed in there.