Topic: Modelling Fire

I would like to know how I can to include a curve ISO 834 of fire.
With regards.
Dr. Manuel L. Romero

Re: Modelling Fire

Dear Dr. Romero,

for the modelling of fire in ATENA, it is recommended to use GID
as a preprocessor. There you define the fire loading by specifying
certain temperature history along the heated surface. Currently
there is no direct support for the ISO 834 curve, but you can
define it manually by specifying the temperature evolution history
along the heated surface. I would recomment that you divide
the ISO curve into several intervals about 5-6, in each interval
will be then subdivided into several steps, which will assume
a linear temperature increase.

Please do no hesitate to contact us in case you have
more questions.

With best regards

Jan Cervenka

Re: Modelling Fire

A quick question which relates to this one:

If I have defined multiple load intervals (e.g. 1,2,3) in GiD for AtenaStatic, then these loading intervals are applied in the calculation one after another, correct?
So if the first interval is a temperature load and the second an external force, the external force is applied once the temperature load is finished.

However, if my previous statement is correct, does the model continues to take into account the temperature of the concrete and reinforcement during the second interval (during the loading)?
=> Is the temperature distribution within the concrete assumed constant during the second loading interval?

Thank you very much.

Best regards,
Ruben

Re: Modelling Fire

> If I have defined multiple load intervals (e.g. 1,2,3) in GiD for AtenaStatic, then these loading intervals are applied in the calculation one after another, correct?

Yes.

> So if the first interval is a temperature load and the second an external force, the external force is applied once the temperature load is finished.

Yes.

> However, if my previous statement is correct, does the model continues to take into account the temperature of the concrete and reinforcement during the second interval (during the loading)?

Yes, load are incremental. In other words, "0" means "no change" (of the prescibed displacement, force, temperature; imported thermal results are applied as thermal load in static analysis).

> => Is the temperature distribution within the concrete assumed constant during the second loading interval?

Yes. You can check this looking at the ELEMENT_TOTAL_TEMPERATURE values in runtime or postprocessor.