WUFI

Hi All,

I was wondering if there are any recommendations on how to simulate an internal wall (CLT), that is sitting on a ground floor slab (ground bearing, concrete slab on grade) that was in contact with water during its construction phase?

I would like to investigate how this might dry out over time or if it will create a problem at the base of the CLT.

There would be no 'External Climate' , just the ground below and internal climate above.

Any guidance or watch-its appreciated thank you!

Regards,

Lee

Dear Lee,

you can create a climate with CreateClimateFile.xlsx in the programs tools folder usually here: which contains the temperature of the ground as well as rain for every hour during the suction process. The RH can be set at 100% during suction time.
Regarding the temperature, have a look in our guideline on typical constructions for basement:
https://wufi.de/en/service/downloads#ty ... structions

Further you need to model the CLT from its single layers (eg material XLam).

Christian

Thank you for the response Christian, this is reassuring as it aligns with my approach.

I did have one further question and that was when to use the Soil DIN vs Soil FSP.

If I use Soil DIN in my case, with a representative temperature curve and RH set to 100% I get significantly lower moisture in the base of the CLT.

If I use Soil FSP, when I create the climate file using the same temperature curve, RH at 100% constant and Rain at 1000 for every timestep, the moisture in the CLT is off the charts.

For context the, soil is the bottom layer, then there is concrete slab and above this is the CLT. I am running cases both with and without a DPC under the CLT too just to see the behaviour.

Many thanks and best regards,

Lee

Dear Lee,

the difference between DIN and FSP is the moisture storage and liquid transport.

Soil DIN (DIN = German Standard Institute) is derived from the standard which only contains basic values. It uses a internal moisture storage function based on the porosity and more important - it does not contain liquid transport coefficients. Because of the missing liquid transport this material does not absorb rain from the climate file. Therefore it is not suitable in your case.

Soil FSP (FSP is the German shortcut for moisture storage function) has been expanded by a moisture storage function closer to that from soil and as well includes liquid transport coefficients. So this one would be the one to use for standing water.
The standing water in the soil might lead to a high liquid transport through the concrete slab if there is no sealing below or on the concrete.

For your interest: there are some further soil materials in the North American Database -> Soils

Christian