Hello Omar Alfisi ,

Some more information are needed in order to make your question clearer.

The second image contains the experimental results that you want to compare with the numerical solution? From the image of the model, the boundary conditions are not clear. Is this beam loaded in 3 points bending?Which element of the model did you choose to create the plot? Keep in mind that the strain that you asked from Abaqus to output is the logarithmic strain and in the first plot your x-axis is time and not the strain.

Hello Eleftherios Tsivolas

I am really grateful for your replying, my task is to model a reinforcement concrete beam and to obtain stress-strain curve and force- deflection, so i used CDP and i used the parameters as showed in my questions, so my beam is simply beam with two forces and i used boundary conditions “hinge and roller” see the attachments, and the second photo is stress-strain i obtained it when i loaded my beam with 40 kn in each side so my supervisor said the beam should fail but as much as i load the stress keep staying constant so i don’t know why it doesn’t fail, the stress supposed to go down right after while?, can you check for me if my input data is correct? and why the beam does not fail?

Best Regards

I believe that you need more data than a row for CDP to specify the stress decrease. For example 3 rows with increasing strain and decreasing stress for both tensile and compressive behavior. You also need to input from the suboptions damage vs inelastic strain data.Also, make sure you have asked the appropriate output requests from the step, especially DAMAGEC and DAMAGEF (See manual for more information).

This following link might help you with the input data but you probably need to calibrate your material to follow your experimental results.

https://www.youtube.com/watch?v=FaK4eRzrLoE

let try this data a take a look.