Hello
I am going to build a mezzanine in an existing shed, to do this I would like to determine the sections of the master beams and joists in order to transmit them to the sawyer,
in the SW library there is the wood/oak material only the coef is missing. Fish, modulus of elasticity etc, how to create a customized material,
thank you in advance
Data for Softwood Mass Timber
Additional info
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okay, only to make a simulation, with the choice of the pine, SW tells me when I apply this material that 1-the Poisson coef will be equal to zero 2-that the modulus of elasticity must be greater than 0, in short, these fields not being filled in, impossible to continue/make a simulation
Thank you
Hello and thank you for your previous answers
There you go, I did as said in the SW help, i.e. edit a custom material and the simulation is not done - cf the 3 imp screen, is there anything I omit, don't do well???
Hello;
If the material is not declared in the 3D component before preparing (launching) the simulation study then it will have to be declared directly in the study tree.
But if I trust your screenshots (not very readable), I wonder if the values entered for your material are correct:
According to this website:
You should have a value of: 10,000,000,000 N/m² for the modulus of elasticity.
(Beware of conversions).
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indeed, mistook me in the conversion of the modulus of elasticity between MPa and N/m²
Thank you, the simul works!!
Hello @Alfoncpasmamob
I do not recommend using Solidworks Simulation for simulation on wooden objects in particular.
Because the values of the constraints given in Mpa are very theoretical.
The wood is totally inhomogeneous and the values given vary completely according to the characteristics of the wood. Moreover, the values are indicated as generally accepted values.
Compare soldidworks- simu values with profession charts
Also, looking at your screenshots, the run-ups and loads are not correct. For loads, they cannot be rigidly recessed.
I think you could at least change the anchors at the end of the beam, your fixing points act as if there was an undeformable connection of your walls.
Sorry for my remarks but I couldn't let you take any risks. Ask for the opinion of a real carpenter who will tell you in two minutes if your assembly holds up (the beam).
Kind regards
PS: it would be a shame if your mob ended up crushed under a beam even if the latter doesn't run 
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To deepen what @Zozo_mp says:
In material strength (RDM), the most common hypothesis is to work with isotropic materials, i.e. with mechanical properties (Young's modulus, yield strength, etc.) that are the same in all directions.
However, wood, and therefore oak, is an orthotropic (and more generally anisotropic) material.
This means that its mechanical properties depend on the direction:
- Longitudinal direction (along the fibres) → the wood is very strong (high Young's modulus).
- Radial direction (perpendicular to growth rings).
- Tangential direction (tangential to the rings).
These last two directions (radial and tangential) have much weaker mechanical characteristics.
Consequences in RDM
- If we model an oak beam as isotropic, we make a rough approximation.
- For basic calculations (e.g. in traditional framing), it is often simplified by assuming isotropy in order to be able to apply the usual formulas for bending, shear, etc. directly.
- In reality, wood is orthotropic : its behavior is defined by 9 independent elastic constants (3 Young's moduli, 3 Poisson coefficients and 3 shear moduli).
Conclusion: An oak beam is not isotropic. In RDM applied to wood, we sometimes choose the isotropic approximer to simplify the calculations, but it is an approximation. In fine design (wood mechanics, glulam structures, dimensioning according to Eurocode 5), its orthotropic character is taken into account.
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Thank you for your valuable advice
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