How does the 2nd floor bearing wall load be transfered to wall below? 4

[ykmz]

It is hard to understand some common details on residential construction. Here is one. Most roofs are built with roof trusses, which can have long span like over 20 or even 30 feet. The bearing wall take quite a big load. But when the floor joist underneath is parallel to the bearing wall, the wall only rest on rim joist which is just 1.25" wide. Although there usually has blocking at 32" or 48", that means the bottom plate will span that long. Unless you consider the wall work as a composite beam, I do not see how it works. Does anybody ever worry about this before?

 

[ykmz]

I agree the rim joist can take the load after analysis. The eccentricity will be balanced by a couple lateral force at top and bottom of the wall.