Slab rebar design

[Elisa Monti Di Sopra]

Hello, I’m having some trouble with foundation slabs design. When I assign the shell elements to a group using the wall design box and checking “consider as slab”, if I modify the name assigned to it (i.e. wall_1 to foundation) I am not able to see it in the assign rebar mask: when I select the planar section, the corresponding group name appears only if I don’t rename it, otherwise I cannot assign rebars. Once I understood this problem, I wanted to verify the assigned rebars with the concrete module but when I click on “perform checks” nothing happens, no error pop-up windows and nothing is processed. I tried to extract moments with the wood-armer method to design the rebar myself, but an error pops up saying “node 1: current block: 0 – assign error – index not included in the interval. Non-negative number required and less than the size of the collection parameter. Parameter name: index”. I removed the group assigned to the shell elements from view before using the wood armer method.
I’m using v. 2.3 of Nextfem Designer. I’d like to know if someone had the same problem or if I am doing somethin wrong. The attached model is a simple model of a foundation slab where I encountered the problems described.
Thank you.
Elisa

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[NextFEM Admin]

Hello,
for the first issue, the “Wall__” identifier is needed to assign rebar to a slab or a wall, hence the group cannot be renamed. I needed, you can create another group with a more frindly name.

For the error in checking, you’re using a deprecated script. In your version there’s no need to call the Wood-Armer moments scripts, since from ver. 2.1 the Wood-Armer moments are available directly in view (see Area forces, mm**WA* components) and in tables (see Extract data mask, Area Forces).

If you need to use then in checking, try calling directly the following quantities. Use this as a script in Verifications mask:

@_mxWAbot
mmaxX
@_myWAbot
mmaxY
@_mxWAtop
mminX
@_myWAtop
mminY

EDIT: actual version 2.4 supports also shear checking in slabs.

[Elisa Monti Di Sopra]

Ok thank you, I didn’t know that the wall_ identifier is required. As for wood-armer moments, I used a post from 2019 about designing slabs with this method, since I didn’t find the topic on the user manual, so thanks for the clarification.
I still can’t perform checks on assigned rebars though, or use the static rebar design option, clicking the button “perform checks” in both cases doesn’t do anything.

[NextFEM Admin]

Static rebar design does not perform design on slabs. Checking should work: maybe you’re requesting checks on combinations (default optionin Verifications mask), but you don’t have combos in the model. Select “ALL” for load case.

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