secondary concrete cover

[ticas]

Imagine there are two vertical girder rc beams on left and right. And in between them is a secondary beam with its top bars over the top bars of the girder beams. This means the secondary top bars are higher than the girder top bars. If you use 40mm concrete cover on the left and right girder beams and assume the pouring is level, then the secondary beam would only have 20mm concrete cover. Any problem with this?

 

[hokie66]

It depends on the effective depths used in the design. Usually, crossing beam bars does not deduct as much as 20 mm from the cover, as the top bars go in the same depth as the stirrups in the other beam.

 

[ticas]

The top bars of the secondary beam is 20mm and they are on top of the top bars of the girder. That means the secondary beam top bar is 20mm higher, so if concrete pouring is level to the girder's top bar at 40mm, then the secondary beam concrete cover would fall short by 20mm.

 

[hokie66]

As I said, it depends on the design assumptions. If you are not the design engineer, ask him.