AS3600:2018 creep factor

Question

Hello all, 
 
 Given that the new update of RAM Concept incorporates AS3600:2018 I think that the following becomes relevant. When determining the creep factor AS3600:2018 has an additional coefficient - k_6, which is intended to account for non-linear creep. Value of k_6 is dependent on stress in the concrete section and so I imagine its calculation must have been incorporated into internal workings of the program, however I have not been able to find any confirmation of this fact. 
 Can someone from Bentley please confirm whether k_6 is accounted for automatically. If not, can we have a method as to how the creep factor calculation changes (compared to what it was before for AS3600:2009). 
 
 Many thanks

Karl G · Accepted Answer

The k6 parameter is not accounted for automatically by the program. The load history deflections continue to be based on the ACI 209 model for all design codes and the creep factor and shrinkage strain that the user inputs. 
 If the k6 factor is not 1 and needs to be considered, you would need to determine an appropriate value outside the program and use it to determine the final input creep factor. Note that the stress is likely different from load step to load step and even element to element, the best you can do is determine one factor that would be used for all areas and all load steps.

AS3600:2018 creep factor

Top Replies