Topic: Reduction of compressive strength due to cracks

Dear Sir,

I got a question regarding the reduction of compressive strength due to cracks (rc,lim).

The default value for the rc,lim in the SBETA material model is 0.8, but the default value in the 3D Nonlinear Cementitious 2 material is 0.2.

The picture next to it shows that this value should be multiplied by the compressive strength:

fc,ef = rc x fc

This insinuates that with a rc of 0.2, the reduction is 80% instead of 20%. Should the default value of 0.2 be changed into 0.8 like in the SBETA material model?


thanks in advance,

Jesse Schut

Re: Reduction of compressive strength due to cracks

Dear jfnschut, yes, in NLCem2, the value defines the minimum value after reduction (as you write, 0.2 means the compressive strength can be reduced down to 20% of the original value).
As the 2 material models are quite different, it is not possible to set the NLCem2 properties to make it behave exactly like SBETA, not even in a plane-stress model and with all parameters set in some kind of equivalent way.

If you have some evidence the reduction limit of 0.2 if too conservative in the situation you are modelling, of course you can change the value.