Topic: High initial stiffness

Hello everybody,

I'm using CC3DNonLinCementitious2User concrete model in modelling the effect of basalt fibre effect in flexure.
I compare between the experimental and model load-deflection curves to state how efficient the model is. I almost have everything right (Max displacement, Max load,..) except the initial stiffness. The model model has a high initial stiffness which makes the two curves parallel to each other.
Any help regarding this point ?

Thanks and happy new year!!

Re: High initial stiffness

Dear karim.attia.1, happy new year to you, too.

I would suggest to first of all check if the initial stiffness is not underestimated in the experiment - this happens quite frequently, typically some initial freeplay or local plastifications are responsible for the difference.

You can also send us the graph comparing the measure and calculated Load-Displacement curves + your model + some sketches&description of what you are modelling (ATENA Troubleshooting, 2.1.1).

Best regards.