I am performing structural simulation on a building made of concrete elements for a student project. The slabs and walls are in reality divided in floor panels and wall panels assembled with joints, but in the simulation I assume that it is a rigid construction and I am considering as elements whole slabs and walls.
I am using the “Shell section” component in order to see what values of Shear, Normal Forces and Moments are applied on diferent points of the building. In order to proceed with my task, I need to apply the same forces on a single floor/wall panel and optimize it s cross section ( I am using the “Optimize cross section” component.
In order to simulate the same force values I found from the 1st simulation I am thinking of applying the values as point-loads in order to have the same values as the results from the “Shell-Section” component (kN/m). My question is how can I simulate the different forces Shear/Moments/Normal? (I don t know much about structural engineering). Can I simulate them using different vectors? for example x or y vector for the in-plane forces of an horizontal panel? or is my approach completely wrong and I need to do it with loads kN/m2?
Hello @theogerg,
when applying the distributed loads via point loads you have to take into account the distance between the nodes and the angle between the line-segments of the naked edges. This can get rather complicated.
Why not optimize the cross section of the elements in the original model?
– Clemens
I thought that since in the original model I used whole elements in stead of separate panels, maybe the results wouldn’t be the same.
So if I perform the cross section optimization to the whole-slab-model, then would it make sense to take the maximum thickness of the optimized whole slab and use it as my panel thickness?
In order to have the same point-position on the single panel, I divided the whole slab into the size of panels that I am using (this was not taken under account in the simulation) and then chose the panels which contain the points with the higher results from the “Shell section” and placed them on the single panel using the “move to point” GH (Point A ont vertice of the panel in the model, point B the same vertice od the single panel model). I thought this could create an accurate position. If this doesn t solve the problem that you mentioned in your answer, then I will perform the cross-section optimization to the whole model.
If this solves the positioning problem, then the last thing that I think remains to do is to use the right way to apply the forces (right vectors etc), which I found from the “shell section” results. In that case, do you know how I could do that?
I am not sure, whether I understand you correctly. Via the input-plug ‘GroupdIDs’ of the OptiCroSec-component one can specify groups of elements which shall have the same cross section. This works for beams and shells (see the manual).
Regarding your last question: You can use point-loads. In order to do this one needs to sum up the distributed cross section forces along the length of influence around each node where point-loads shall be applied.
– Clemens