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Different results in cohesive zone modeling for the same data input

abc123ali

Mechanical
Nov 6, 2023
86
Respected ABAQUS users, I would like to request the solution to the issue regarding making the contact in cohesive zone modelling.
1. When I used the node to surface contact in the interaction by selecting node as slave and surface as master in the discretization method the output results showed very high values for the output force-displacement curve compared to the input. why? ;This is when I used contact model cohesive zone
2. When I used node to surface as discretization method but used the master and slave surfaces and not the master surface to slave node set the results comes out closer to the input data. Why?; This is when I used contact model cohesive zone
3. When I used surface to surface discretization method and select the both surface; master,slave and not the salve node with master surface the output results shows a little far values from the original. why? This is the contact model cohesive zone
4. When I model the system using cohesive zone elements rather than contact model then the results comes out are far from the input data. Actually the input peak of nominal stress is 6.2 MPa with the contact area of plates which is 61 but when the results comes the peak force is just 325 N but the input data it is 378 N. Here I used tie constraint with node to surface and surface to surface but the results are not fine.
5. Refining the mesh is not affecting the results in all the cases but the mesh shapes. The inp files are attached here
6. The variation in result occurs when the applied displacement in the load module is from 2.4 to 2.7 but the failure disp is kept constant to be 2.4. The force output peak changes from 360 to 325 with disp 2.4 to 2.7 mm respectively. why??
7. Is it possible for using the node to surface and conversely surface to node between the two interacting surfaces for better results?

kindly suggest me a solution
 
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Are you using contact pairs or general contact ? Abaqus/Standard or Explicit ?
 
I am using surface to surface standard contact in the interaction module while using static general in the step module
 
I am using general contact standard surface to surface and static general as a timestep
 
Ok, so contact pairs and Abaqus/Standard then. But then the cohesive behavior is available for the node-to-surface formulation but not for the finite sliding surface-to-surface one (not to be confused with how contact pairs are called Surface-to-surface contact in Abaqus/CAE).
 
Respected ABAQUS users, Also I want to request felling the newly modified platform a bit difficult to use as the best of my knowledge I uploaded 4 inp files for the assessment yesterday but here these files are not displayed as if these were attached or not and the time displayed for this attachment was today around 4 Am and not 7;34 pm but it is shown like this here. After sending the reply here it is also not displaying so I got confused and sent here two times. Also it is not appeared that if you replied here or not. Kindly assist
Thanks for cooperation
 
Last edited:
Respected ABAQUS users, Also I want to request felling the newly modified platform a bit difficult to use as the best of my knowledge I uploaded 4 inp files for the assessment yesterday but here these files are not displayed as if these were attached or not and the time displayed for this attachment was today around 4 Am and not 7;34 pm but it is shown like this here. After sending the reply here it is also not displaying so I got confused and sent here two times. Kindly assist
Thanks for cooperation
You can report issues with the new forum here: https://www.eng-tips.com/forums/new-forum-platform.100108/
 
Ok, so contact pairs and Abaqus/Standard then. But then the cohesive behavior is available for the node-to-surface formulation but not for the finite sliding surface-to-surface one (not to be confused with how contact pairs are called Surface-to-surface contact in Abaqus/CAE).
So may we use surface to surface with small sliding in abaqus standard for cohesive zone model. Is there an option if we use master and slave surface as a contact but use node to surface as a discretization method as selecting nodes is difficult sometimes may require python or other plugins. Thanks
 
Yes, you can use surface-to-surface formulation with small sliding or just node-to-surface. Only surface-to-surface with finite sliding is not supported for cohesive behavior.
 

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