Collin_St203
Structural
- Jan 25, 2022
- 9
This project has both RC beams and slabs and as I am using design strip to help design my slab. However I found some design strips fail in either flexural or shear without reinforcement @ where RC beams are close.
So I create this simplified model trying to understand what is happening behind the scene when design strip is overlapped with beams.
Plan is 20m x 6m with 200mm x 1000mm RC beams. 50kN/m line load applied to 2 beams as shown.
For study, I create a design strip in the middle with width to match the beam: 200mm
I can see from the result that either the moment or shear in the beam is a lot smaller than in the design strip, meaning the program is not using the the beam results for the design strip, which is good. However, even so my strip still fails in shear without reinforcement.
I would expect that the force that design strip picks up is small enough to let it pass since I have a beam here. I know in this location it is a beam so I dont need to use design strip for this area. But, with my current project, even if I widen my design strip it still give me failure sometimes and I don't want to create strips in such a way that where beams are it will be skipped because it will be too time consuming. (ie I have to run design strip to overlapped with beams)
So I am wondering what is behind the scene when design strip is overlapped with beam in ETABS/SAFE?
So I create this simplified model trying to understand what is happening behind the scene when design strip is overlapped with beams.
Plan is 20m x 6m with 200mm x 1000mm RC beams. 50kN/m line load applied to 2 beams as shown.
For study, I create a design strip in the middle with width to match the beam: 200mm
I can see from the result that either the moment or shear in the beam is a lot smaller than in the design strip, meaning the program is not using the the beam results for the design strip, which is good. However, even so my strip still fails in shear without reinforcement.
I would expect that the force that design strip picks up is small enough to let it pass since I have a beam here. I know in this location it is a beam so I dont need to use design strip for this area. But, with my current project, even if I widen my design strip it still give me failure sometimes and I don't want to create strips in such a way that where beams are it will be skipped because it will be too time consuming. (ie I have to run design strip to overlapped with beams)
So I am wondering what is behind the scene when design strip is overlapped with beam in ETABS/SAFE?
