multi story wood structure stud wall plates

huangyhg

multi story wood structure stud wall plates
i think i go around and around with this situation everytime i look at my detail.  i have a 4 story wood structure (hotel) that is framed with 2x6 stud walls and 24" deep pre-engineered roof trusses.  my questions lies at each level where the stud wall sits on my trusses.  i usually provide a 2x6 sill plate that sits on my floor sheathing that sits on a continuous 1 1/2" rim board.  the trusses butt into the rim board and sit on a double top plate of my stud wall.  how do i analyze this system when transfering my vertical stud loads from above?  is it just and accepted practice just to stick with a single sill plate and a double top plate?  i usually don't worry about this but with this being 4 stories and all i probably won't sleep so well.
if these bearing walls are also shear walls, depending on the load to the wall, the perimeter   
if you are concerned with gravity loads, here is how i look at it:  the rim board will transfer the stud loads from above into the studs below without bending the double top plate below.  the double top plate should be checked for bending if the floor trusses at the floor in question land between the wall studs below.
daveatkins