Clinker

[olivir]

Do you have information on clinker ("mâchefer" en français), resulting from coal combustion, used in construction early in the last century ? I didn't see in any of your databases...

[Christian Bludau]

Dear Olivir,

we have no clinker in our database. The clinker itself most time has a low water absorption as the surface is sintered. So in this case the mortar joints are the crucial factor. In 2D you can try to model that as stone and joints, in a one-dimensional model you can try to generate a material with effective values for water absorption and transport.

I once adapted the "solid brick, historical" and used it for a calculation based on some values for clincker i got. One was a kind of destructed, showed some cracks and had a quite high a-value of about 1.65 kg/m²sqrt(h) and the other one was an actual one with a really low a-value (0,002 kg/m²sqrt(h)).

klinker.zip

Contains a clinker, old, destructed, with cracks, a-value 1,65 kg/m²sqrt(h) and a new one, quite tight, a-value 0,002 kg/m²sqrt(h)
Attention: This material is not measured or validated, there is no guarantee, if the parameters are right.

(2.51 KiB) Downloaded 660 times

Attention: This material is not measured or validated, there is no guarantee, if the parameters are right. Further bricks are generally spoken very different. Please only use it to get an idea of the material.

Regards,
Christian

[olivir]

Thank you, Christian !
I understand there's no guarantee but it's mostly to compare quickly to limestone. Besides, what difference is important to you between this 2 materials ?

[Christian Bludau]

Important is the a-value, in this materials the water transport is derived from the a-value. The higher it is, thhe higher is the water absorption and the transport (suction and redistribution). Further important may be the water vapor transport (µ-value).
Christian

[olivir]

Is a-value (water absorption coefficient) directly accessible in material datas ? I don't find it...

[Christian Bludau]

The a-value can be used to calculate the transport coefficients. It appears by switching the transport coefficients of suction and redistribution to generate:

The a-value appears in the material data, if generate is chosen for the transport coefficients for suction and/or redistribution.
Attention: in Wufi you have to enter the unit seconds not hour (kg/m²s^0.5)

a-value.png (83.57 KiB) Viewed 13412 times

Attention: In Wufi you have to enter the unit with seconds (kg/m²s^0.5) not hour (kg/m²h^0.5).

Christian

[olivir]

How to obtain the a-value that for a non-editable material from one of your databases ?

[Christian Bludau]

You have to unlock the material before, then it will work....
There is something looking like a lock in the upper right corner of the material data window.
Christian

[olivir]

Oh sorry, it was obvious enough ...
Why I have no a-value for Krensheimer Selly limestone ?

[Christian Bludau]

In this case the water transport was not determined. The reason is probably, that the limestone is quite tight without pores and there is no significant liquid water transport.

Chirstian

[olivir]

Is there a "classic" limestone with a a-value in one of the databases ? One I didn't see ... (WUFI needs a search engine )

[Christian Bludau]

As far as I know there is one in in the MASEA Source, but this one has a quite high a-value because of the cracks in the stone. I´m not sure how realistic that is.

We have a new database module in development right now which contains a search function, but this will need much more time at the moment...

Christian