Hi

Which kind of interaction did you use? Embedded Region?

Dear Salvio,

What type of element did you use for stirrup and rebars. It is better to use same continuum element both for stirrup and rebars. Because, there may be a chance for error in joint interface compatibility. What i am saying if you have two different elements then it is difficult to connect them. The joint b/w stirrup and rebars can be connected using link element i.e. node to node connectivity. In ABAQUS many type of joint elements are there, you choose link element for connecting two materials. I suggest you to read ABAQUS manual for further understanding in this regard. All the best..

I prefer that you connect the stirrups directly to the reinforcement.

Hi all, I'm using embedded region for the interaction between reinforcement and concrete. Is that all I need to do?

What surprises me is that I run a certain beam without any stirrups and get a certain capacity. Then I run the same beam with stirrups and the capacity is the same. The only difference is that the behavior becomes more ductile. In the experiment the capacity increases by 33% when stirrups are added.

This beam is shear critical and I can observe the correct failure mode from the stress contours.

Thank you.

Mohannad, how do you connect them directly to the reinforcement?

Dear Salvio,

You need to study the response of concrete beam subjected to vertical or lateral load. When you are simulating the reinforced concrete beam then what is the need to consider it in two different component mean..reinforcement and concrete..You use Drucker - Prager model with material properties of Youn'g's modulus, unit weight and Poisson's ratio of concrete..If you want to study the role of reinforcement then it may need to simulate separate..if at all you want to connect then link element only the best option..you look to the manual for connecting element.

Hello,

Did you solve that issue ?? and how?? I have exactly the same problem.

Thank you

Hi Sophia Limam ,

I was able to get good results after all, but not by changing the rebar-stirrups connection. Instead, I modified the angle of dilation of the concrete in the CDP model. In my final beam models I used both stirrups and rebars embedded to the concrete, nothing else. When they are embedded to the concrete they move together with the beam, so if two bars meet at one point they will move together at that point even if they are not connected. This may be enough to connect them.

Hope this helps. Let me know if you have more questions.

Best,

Sálvio.

Dear All,

I am using CDP. My understanding is that mainly in solid elements (concrete), you can model reinforcement as truss elements (preferably) embedded in concrete. To account for dowel action and bond due to longitudinal reinforcement, some sort of tension stiffening can be introduced to uniaxial tensile stress-strain relationship of concrete. However, when it comes to stirrups how do you generally define their effects due to both shear and confinement? I am almost certain that embeddment of stirrups in concrete only does not show neither of these effects as I have carried out some trial modelling (Stirrups addition had marginal to no effect on my RC load carrying capacity when in real experiments that affect was upgraded by around 30%).

Thanks in advance

Hi Salvio Aragao Almeida Junior What value you use for dilation angle? and can you explain how it affects the results?

Many Thanks