Load transfer method on load panel
Different methods are available for the loads transfer via load panels :
![Load transfer](/sites/default/files/styles/embed_medium/public/images/2022-12/Load%20transfer.png?itok=SDSjs-Ov)
Which one to choose?
By default, the method is « Tributary area » : loads are distributed according to the break lines.
But this method is available only with uniform surface loads on the whole panel.
In case of partial surface loads on a panel, or triangular loads, or trapezoidal loads, …, a warning will be displayed because we need to use another method.
Standard
The load is distributed according to factors.
In the above example, the load would be distributed by 1/3, 1/3, 1/3 on each bar, because factor 1 is defined on each bar (even if the load is a linear or a point load in a corner of the panel).
The distribution doesn’t take into account the loads locations, but rather the defined factors.
This method is less used than the others.
![Standard](/sites/default/files/styles/embed_medium/public/images/2022-12/Standard.png?itok=qMsXhwX_)
Accurate (FEM) - all load transfer directions
When you use a load panel with the Load transfer method “Accurate (FEM), following analysis is performed (see also our helppage FEM method):
![Accurate FEM](/sites/default/files/styles/embed_large/public/images/2023-09/Accurate-FEM.png?itok=5sDexd5u)
The solver uses the mesh setting 'Average size of panel elements [m]':
![Mesh setup](/sites/default/files/styles/embed_medium/public/images/2023-09/Mesh-setup.png?itok=Zke573o9)
For the FEM load transfer methods, there are options 'hinged support' and 'fixed support'. The distribution of loads is done following the indicated, giving for example the following results:
![Transfer](/sites/default/files/styles/embed_medium/public/images/2023-09/Transfer.png?itok=B5CT1pAQ)
The analysis is done with fictive 2D elements with the following parameters:
- E modulus = 1 GPa
- Poisson coefficient = 0.25
![Orthotropy](/sites/default/files/styles/embed_medium/public/images/2023-09/Orthotropy.png?itok=KDqS054k)
Accurate (FEM), fixed link with beams, X and Y 50%
![Fixed 50-50](/sites/default/files/styles/embed_medium/public/images/2023-09/Fixed-50-50.png?itok=qCzIWXQY)
Accurate (FEM), hinged link with beams, X and Y 50%
![Hinged 50-50](/sites/default/files/styles/embed_medium/public/images/2023-09/Hinged-50-50.png?itok=c2az0iJV)
Accurate (FEM) - 1 direction
If the load transfer direction X and Y are set differently, for example 80% and 20%, then the parameters of the orthotropy are calculated proportionally.
For load transfer direction set to X or Y, the E1:E2 ratio is taken as 80:20% and E = E1 + E2 = 100%.
- D11 and D44 = 80%
- D22 and D55 = 20%
- D12 and D33 = 50%
![Orthotropy 80-20](/sites/default/files/styles/embed_medium/public/images/2023-09/Orthotropy-80-20.png?itok=jZ8p9uEM)
Accurate (FEM), fixed link with beams
![Fixed 80-20](/sites/default/files/styles/embed_medium/public/images/2023-09/Fixed-80-20.png?itok=rS3JPHyS)
Accurate (FEM), hinged link with beams
![Hinged 80-20](/sites/default/files/styles/embed_medium/public/images/2023-09/Hinged-80-20.png?itok=-s7jdS_7)
Example
Accurate (FEM), fixed link with beams
This method is close to the tributary areas method, because the distribution is divided by 2 on each side.
![Precise FEM](/sites/default/files/styles/embed_medium/public/images/2022-12/Precise%20FEM.png?itok=qE-ZFIrH)
Accurate (FEM), hinged link with beams
![Precise FEM - hinged](/sites/default/files/styles/embed_medium/public/images/2022-12/Precise%20FEM%20-%20hinged.png?itok=CCmjupLX)
Let’s have a look at the simple example below:
![accurate FEM](/sites/default/files/styles/embed_medium/public/images/2022-12/accurate%20FEM.png?itok=Dy_Rb6h4)
![Accurate FEM hinged](/sites/default/files/styles/embed_medium/public/images/2022-12/Accurate%20FEM%20hinged.png?itok=CAZXoHLw)
![tributary area](/sites/default/files/styles/embed_medium/public/images/2022-12/tributary%20area.png?itok=-QxJGDnh)
Let’s apply a surface horizontal load on each panel.
Results are in line with the previous description of this option:
![results load panels](/sites/default/files/styles/embed_medium/public/images/2022-12/results%20load%20panels.png?itok=bdM-Wns4)