Composite materials approach

[stefan]

See also this older (closed) thread:

Calc-U-value-wall-of-composite-wall-with-its-own-frame 

For a research project, we are looking at methods to properly capture actual material composition for LCA and other simulations. In Archicad, materials are homogeneous. However, for a more accurate simulation, many "materials" are actually aggregates of multiple components in a particular fraction (e.g., facade brick + mortar = facade layer).

How would you manage this inside Archicad?

Invent a "fake" composite material, where the different fractions are taken into account (weighted)?

Override the values of the brick to also take a fraction mortar and other components into account?

Or ignore Archicad and do the calculations elsewhere?

Our project partners showed a demonstration inside Revit, where they added custom parameters to the material, which in themselves reference other materials. This way, they can define the composite and the components all as regular materials. (Needless to say, this doesn't transfer well to other environments - and no way to bring this in IFC).

[lopezfigueroa]

I think that if your intention is to use the data for simulation or IFC purposes, the ideal would be to create a construction material with the data corresponding to the composite per layer. For example, reinforced concrete has a standard weight of 2400kg/m3 and known physical properties.

Obviously the work of creating composite construction materials is laborious but necessary, something similar happens in terms of structural calculation, the particular weight of each layer of the wall is defined to consider a total per m2 or m3. The detail of each composite material can be quantified using properties and expressions whose data can also be transferred to the IFC, it is also laborious but it can be done.

We would like to reach extreme details where we can analyze each construction component, but being practical, many of these components are estimated by m2 or m3, to which a waste or performance factor is also added.

Uncertainty in data is a factor that we have to live with constantly, there is no formula that covers everything so we resort to constants, just as physicists use them to explain the mysteries of the universe. We can reduce it, but not eliminate it.

A friend developed a label for the cases of the U value, it may help you​
https://www.airc.market/012-u-value-tool

I hope my comments help you, that's what I would do in your case.
Good Luck