On this review of IBC 2006, it states:
"Wood shear walls can resist seismic forces generated by
horizontal concrete but not from concrete or masonry walls per IBC 2305.1.5."
And it doesn't say that the horizontal concrete has to be non-structural. Or, I think they would have called it "concrete floors" if they meant it to be non-structural in nature (engineers usually call horizontal structural concrete as "slabs" and not "floors").
I guess as a side note, if I wanted to use the Hambro composite system supported on wood walls, how would I make the connection so that no seismic force is induced in the sheathed walls? And also, when I looked at IBC 2003 the other day, it appeared you COULD use wood shear walls to laterally support STRUCTURAL concrete (slabs and walls) as long as you met certain conditions. So now in the IBC 2006 they changed it to where you can't laterally support horizontal structural concrete at all??
Right now, I am thinking the following:
1. Section 2305.1.6 pertains to NON-STRUCTURAL concrete exclusively by title, so I will say this has nothing to do with the discussion and I shouldn't have mentioned it previously. It seems poorly worded in that it states "non-structural concrete" and then mentions "concrete floors" separately as if concrete floor topping is different from other types of non-structural concrete.
2. If I remember correcty, Section 2305.1.5 previously pertained to laterally supporting all STRUCTURAL concrete in IBC 2003 with certain stipulations. But now, in IBC 2006 it has been completely re-written to only put stipulations on laterally supporting concrete walls. So should I infer that by them not specifically mentioning horizontal structural concrete in section 2305.1.5 that it is forbidden to be laterally supported by wood altogether now??
So it looks like we are understanding each other completely as this reiterates what you said, but I am seeing it as by them not mentioning structural slabs in 2305.1.5 that they are NOT excluded, where you are seeing that it means they are excluded. BTW, I appreciate the conversation on this.