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@@noamaanshaikh5702 İ think you meant the interaction between the adhesive layer and the substrate. İf it is your question, i should answer it is not necessary in this model, because we didn't model the adhesive layer and the substrate separate from each other. Thismodel is only one part.

@@noamaanshaikh5702 as i remember you are not allowed to use tie or any other BCs for traction separation czm element. Check it.

Yes, you can but be careful about the reasonablity of the chemical reactions.

No I don't.

@@luizgustavodelimapreviero4895 happy to hear that. Thanks for your interest.

In some cases element deletation doesn't work. However, you can check SDEG(the damage parameter) in your contour results and you can consider damage for elements with SDEG more than 0.98.

@@atakhabaz3607 so if I specify the max degradation equal to 0.98 in my mesh control, so the distorted element could be deleted?

@@AlisherAshirbekov the thing that you mentioned is something else. It's the input value for your simulation that indicates the deletation should start when D is 0.98. However, sometimes Abaqus doesn't show the elements deletation. In those cases, you would better to check D parameter from you counter results. And consider If the damage parameter D exceeds 0.98 for specific elements, you can consider those elements to have failed. You can check the D parameter using SDEG.

In this case, the adhesive shows a ductile behavior and this approach can predict final load very well. It should be useful in brittle adhesives as well. The main condition here is that you have got a cohesive failure in the bond line not an adhesive failure.

@@atakhabaz3607 i had 99% of damage, should i play around with G values? because im getting too big values for load and disp also can i contact you for more help?

Nu is considered to be an elastic property. It's not an highly effective parameter. If you don't know the exact amount you can consider it among 0.3 to 0.4 for adhesive layer.

Hi MONO, Since I don't have detailed information about your simulation, I can only guess some probable mistakes. Please check the following: 1. You need to change either the initial stiffness or the Young's modulus in the normal and shear modes. 2. You are not allowed to mesh the bonded line with more than one element in the thickness direction. 3. You are not allowed to change the maximum traction because this parameter is more important than the G value. 4. Maybe you have experienced adhesive failure in your experiments. If so, the interface region is weaker than the adhesive layer itself, which introduces an error in your simulation.

@@atakhabaz3607 Thank you, Dr. Ata. I recalculated Young's modulus, my mesh is alos one element thick, Rest I have left all the default value. We simulate two conditions, one at room temperature and second at higer temperature. So now, my simulation runs, the cohesive elements starts to vanish, but then it stops with an error ..."THE SOLUTION APPEARS TO BE DIVERGING. CONVERGENCE IS JUDGED UNLIKELY." Thank you once again. Regards

"This video has an educational aspect, but please note that it has not been validated or verified by authoritative sources."

Thanks for your interest Imen. It's Ok. I'll go for that soon.

Thanks Dear Houman

Dear Safa, sorry I couldn't get your point. Could you please ask your question more clear and/or with details.

Thanks Dear Amir. Thanks for your time, interest and support. 🙏☘️

Thanks Dear Dr Rahmani for your interest. 🙏🙏🙏

Thanks for your interest 🙏

Thanks Houman.

Thanks for your interest Dear Dr., In order to apply cyclic loading, it is preferable to apply the load using the amplitude, similar to what is done in the movie. However, to simulate the pinching effect, I believe it is necessary to write a subroutine. Within this subroutine, you can introduce a damage parameter D, which ranges from 0 to 1 and is a function of the time period. As the solution progresses and the time step increases, the elastic and plastic properties should be updated by multiplying them with this D parameter.

@@atakhabaz3607 Hi Thanks you , please have you another easy trick to consider pinching effect ? Thanks

Thanks for your comment but I think it's better to do the analysis by the BCs that you mentioned. If you model any kind of repeated cell including 1/4th, 1/2nd one or two or ... cells of fiber and matix as a representative, it should give you the same results, neglecting that it's periodic or not.

Thank you for your reply. Do you understand how to add complete cellular periodic boundary conditions? In particular, how can the nodes at corners and edges be handled to prevent over-constraint? Thank you.@@atakhabaz3607

Thanks Dear Muzafar. I just want to make videos of own interesting experiences. My main fields of study are related to mechanical point of view on adhesives, frps and polymer and solid materials interface. This video is also a fundamental and important study that can be used in such studies. All in all, i appreciate your comment and try to do my bests.

Thanks a bunch Dear Youness for your time.

Thank you! Cheers!

Thank you for your interest. Actually here we also used the triangular or bilinear CZM. this triangular damage model indicates using 3 individual parameters of 1. initial slop (or elastic Props), 2. the maximum amount of traction (Sy), and 3. the area under the triangle traction-separation diagram (Energy at failure).

@@atakhabaz3607 then I Can do thé same to get parameetrs. Thank you so much

@@atakhabaz3607 Hi I am working on DCB test , I made all steps but when I compare the RF at the reference point I find thant FEM force is so high compared with experimental force. I don't find the source of problem, Do you have any idea please.

@@imendebbabi8071 I think you have got the science border. But according to my experience it can be due to some reasons. 1. You maybe use a brittle adhesive in experiment. (If you use Araldite2011,then it was cured in room temperature maybe). 2. The domenant fracture area in DCB test is adhesive.

I mean Adhesive failure not cohesive.

Please provide me with your project. You can contact me via my Gmail. khabaz65@gmail.com

Thank you for your insightful question. As you mentioned, in this case, S22 represents the peel stress. When it comes to shear stress, we cannot consider any Sii stress form as shear stress. Sii always represents the perpendicular stress in the ith axis. Shear stress always requires two individual axes to determine it properly. One axis indicates the applied plane, and the other indicates the stress direction. Therefore, in this 2D problem, S12 is the shear stress, not S11.

I sincerely appreciate your generous support. Thank you, Dr.

Thank you for your interest. I apologize if I didn't fully understand your question. From what I gather, you're asking about the relationship between stress, overlap length (X axis), and shear stress in a joint. In this context, we can consider the stress acting along the overlap length as shear stress, while the stress acting perpendicular to it (along the Y axis) can be considered as peel stress. It's important to note that this type of joint experiences both shear and peel stresses, with shear stress being the dominant factor. To further explore the effects of peel stress, you can simulate other joint geometries, such as a butt joint. This will allow you to observe and analyze the peeling effects more prominently and understand how they influence the joint behavior.

Thanks for the visit

Welcome!

First, I would like to express my sincere gratitude for your interest in the video. Regarding your comment, I agree that this line is insignificant if the element is chosen to be in a plane stress condition. As you mentioned, opting for plane stress with thickness provides more precise and accurate results.

Thanks for your interest. Sure. Just send an email to: khabaz65@gmail.com

Thanks for your interest.

I really appreciate Dear Professor. I am waiting for it.

Thanks for your interest

Any individual model has its own condition but sure I will.

Thanks

Thank you Hooman🙏

Thank you for your comment! In Fourier Transform Infrared (FTIR) spectroscopy, the wavelength span typically covered is in the infrared region of the electromagnetic spectrum. The infrared region ranges from approximately 700 nanometers (nm) to 1 millimeter (mm) in wavelength. FTIR spectroscopy is specifically used in the infrared region because it allows us to study the vibrational and rotational modes of molecules. Different chemical bonds and functional groups exhibit characteristic absorption bands in the infrared region. By analyzing these absorption bands, we can gain valuable insights into the molecular composition, structure, and interactions of the substances under investigation. The infrared region is particularly useful for studying organic compounds, polymers, minerals, and many other materials. It provides a unique perspective on chemical bonds and molecular behavior, making it an essential tool in various scientific fields, including chemistry, materials science, pharmaceuticals, and environmental analysis. Even though this video specifically focuses on the normalization of the curves, I really appreciate your brilliant question for clarifying this issue. Thank you for your valuable input Dear Dr. Behzad!

Thanks a bunch Dear doctor Asghar. Warm welcome to you.