Time-dependent development of the material properties of concrete

SOFiSTiK Teddy
,
1

Hello,
as part of my research, I would like to generate parametric folded-plate models of composite bridges in order to investigate the development of stresses in the bridge deck slab during the construction phase.

At present, I am looking for a way to model the time-dependent development of strength, particularly tensile strength is of interest, according to DIN EN 1992 or the Model Code.

Unfortunately, I have not been able to find any relevant information on this either in the manuals or in the forum.
Could someone perhaps help me with how I could manually adjust or implement this?

Thanks in advance

2

Hi there

the time depending stiffness development is already included in the CSM

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just take a look at the csm31_design.dat example in the example files.

But be cautious: the stresses calculated by command SPAN in AQB are referring to the E-Modul defined within AQUA.

Maybe the command SV FACE helps you

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Make yourself a simplified example and test it out.

3

Hi,

thanks for the response.
After posting yesterday i found the time depending stiffness development in CSM.
And i got it verifierd for concrete type “S”,”C” and “R” in a small Benchmark.

Regarding the calculation of stresses etc., please correct me if i’m worng, i understood the following:

  • IN CSM all stages are defined with the correct time between them (T0,TS) incl. all c+s steps
  • CSM defines ASE runs for all loadcases/ construction cases
  • ASE uses the correct age of the concrete via “T1” which is calculated by CSM
  • performing a non-linear analyses with “STEU ASE TEXT ‘SYST PROB NONL NMAT JA’ uses the time depending curve for E-Modules
  • The ASE-Results for the CSM-cases contain all the non-lin. stresses in the concrete and the rebar with consideration to the concrete age

I don’t want to use AQB oder BEMESS because i don’t need any proof.
The non-linear stresses from ASE in the concrete and rebar are enought for me.
I’m mostly interested in the stresses in the concret slab during the construction stages.

Due to that i think the workflow i created should be sufficient for my needs