seismic load resisting system
 

seismic load resisting system
i have a building that is essentially a rectangle. there are masonry walls on two adjacent sides and the other two sides have moment frames. i know it's not an ideal layout, but the architect won't give me braced frames.
my question is what type of lateral system is this considered? it's not a dual system is it? do i have two different systems and therefore two different r factors? the building is only in seismic category a, and it's only two stories tall. i'd like to use r=3 (not specifically detailed for seismic) for the moment frames.
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i believe that for seismic design category a, you simply need to use increased loads, but do not need to use seismic detailing.
if i had to guess, i'd assume you would consider each direction separately.
for sdc a you would probably end up using a seismic load of 0.01w for the lateral seismic response.
it is not a dual system. you would use one r for one way and another r for the other direction...but again, with sdc a this doesn't matter since you would fall under the 0.01w criteria.
a dual system is when you have a shearwall and a moment frame in the same line, sharing load together.