Thank You for sharing this! I had been trying to use the cohesive elements for a while but to no avail even after reading the ABAQUS online documentation. Any idea how to model using more than one part? Like a single lap joint (metal-adhesive-metal)

Thank you for sharing this video, it helped me very much

@hamidst945

7 жыл бұрын

hi. your from iran?

Thank you very much to share this video with us. Could you tell me if in some where I can find 3D model of Double cantilever beam?

Thanks dithoae for your tutoriel. I'm trying to use cohesive elements in a composite material, but it isn't working. can you help me.

Great video man thanks a lot 😊😊

Thank you for the great video, I wonder that if we use fracture energy option insead of the displacement and we have the traction-separation curve, is it the full area under the curve or the area between damage initiation and failure to calculate the fracture energy G ? Thanks.

@FEADith

Жыл бұрын

For brittle material when you dont have plasticity, fracture energy is the energy under traction separation (full area). For material with plasticity, it is the area under the curve excluding the plastic area. Just draw a sketch and it will be easier to understand which part is elastic energy and which part is plastic energy. The damage always associated to elastic energy since it degrades elastic stiffness

very nice video thank you very much

Hello thank you for sharing, i need help to built my UEL can you help me please.

very helpful.

thank you very much

Hi, it's me again. I implemented what you suggested and it worked. Thank you. Now, I'm trying to use the PPR UEL. But I'm in doubt about the units I should use for the fracture energy parameter. Should I use N/m? Because I have 300 N/m and 500 N/m for the normal and tangencial directions, but I realized that you and Prof. Paulino have used a very smaller value.

@heronjd

8 жыл бұрын

+Heron Dionisio I forgot to say that I'm using meters and Newton as my units in Abaqus.

@FEADith

8 жыл бұрын

+Heron Dionisio You can use whatever you want.. just make sure they are consistent with another units.. if you draw your model (with unit length in mind as meter, you also need to use meter. and if the stiffness is 200 GPA and you input the value of 200e9 to the cell of stiffness, then it means you choose pascal as you pressure/stress unit.. in that case, your force unit should be newton..

Hello! Thank you very much for posting this video. What interaction property would you assign if two layers are to be laminated (one of which is sticked to the glue). Hoping to get a reply Thank you in advance!

@praveenvenkateshs.v.2228

5 жыл бұрын

Did you get the answer for you question?

@FEADith

4 жыл бұрын

If you check my recent videos, you might find the answer of your problem.

Thank You

Hi Dithoae, Thanks for sharing the video . I did exactly what you said but there is no element deletion. I assumed the element deletion but in the result, there is an expansion in cohesive elements but no deletion! so two surfaces aren't really separated. Do you have any idea about this issue? Thanks again Hoda

@FEADith

7 жыл бұрын

are you sure you put exactly the same input parameters? try to reduce the Gc (energy at fracture) by half

@HaneefHamzah

7 жыл бұрын

you need to enable status in the F-output, he ticks it towards the end of the video.

@praveenvenkateshs.v.2228

5 жыл бұрын

In mesh module, while defining element type for Cohesive layer you can see an option for element deletion, there you have to check.

hi, thank you for sharing, about cohesive element orientation, is it unnecessary to assign stack direction if you define sweep path for cohesive element part under mesh controls?

@FEADith

2 жыл бұрын

Just make sure to recheck the stacking direction. U dont want in a situatuon where you believe that you got the correct results, prepare report and prented it.. and then realized the direction is incorrect. Normally if you sweep it would be ok.. but once you do partition, the direction can change again..

hi Hi Dithoae, Thank you for your video,I want to ask how you know the dis-max=0.25?

@FEADith

7 жыл бұрын

this number is just sample. but if you to calibrate it, you can plot the stress-displacement curve of a given cohesive model. Then the are under the curve should match with the critical energy release rate (G1c) of the material. In that case, you change the value of dis_max so that the area below the curve match the G1c

@prajwalbharadwaj875

5 жыл бұрын

@@FEADith Do you know how to calculate the stiffness values for the interface elements? (Ess,Enn etc)

@FEADith

5 жыл бұрын

@@prajwalbharadwaj875 it depends on what you are trying to model. If you are modeling a zero thickness interface, you should put value that is big enough to prevent spurious compliance but small enough to facilitate convergence. Value of E=10e5 to 10e8 are generally recommended. If you are modeling real material interface with finite thickness (for example adhesive) you can put real value of adhesive stiffness or usually E = Ereal/thikness of interface. Hope this helps.

@prajwalbharadwaj875

5 жыл бұрын

@@FEADith Thanks for the reply. Just to be clear, for zero thickness surfaces are you selecting a value of thickness T between 10e-5 to 10e-8?

@FEADith

5 жыл бұрын

@@prajwalbharadwaj875 no.. i recommend stiffness with value around 10e5 to 10e8. Not the thickness.

Hi, Can someone please tell me what are the units have been used here for the model? Length is 400m or 400mm?? Also for the stiffness?

Hi. Thank you for sharing this video with us. I'm trying to use cohesive elements in a cylindrical geometry, but it isn't working. I saw you didn't connect the cohesive elements to the other parts with Tie Constraint. How are they connected? Are they sharing nodes? I tried to mesh the parts doing the same thing you did, but it didn't work. The parts don't connect to each other. Could you help me, please? Thank you again.

@FEADith

8 жыл бұрын

You should make all in one part.. So they share nodes. No need to tie. If you want, you can also do it.

@FEADith

8 жыл бұрын

If you wan to make it in clynder.. Let say cylinder wih radius r1 and another concetric cylinder r2.. You can make one cylinder and do partition at r1, r1+0.0001 0.0001 Will be the thickness of the interface. It should be straight forward as in the video.. Make sure you follow all the steps..

@heronjd

8 жыл бұрын

+dithoae Thank you very much. I will try to implement what you suggested.

Hii I liked this video very much. I have a doubt on how to choose the Nominal stress values and displacement of 0.25 and E/Enn etc???....please reply

@FEADith

4 жыл бұрын

Nominal max stress can be achieved from tensile test while the displacement at failure can be calibrated by matching DCB response.

Hello dithoae, first of all thanks for sharing, it is hard to find cohesive behaviour info online and what an experienced person can explain in 15 minutes takes a century to figure out from the documentation... Have you tried using cohesive surface instead of cohesive elements? Best regards.

@FEADith

8 жыл бұрын

+Santiago Restrepo yes, I tried the cohesive surface. they behave the same but implementation point of view is different. In my case, i prefer cohesive element since I can see the deformed cohesive element visually.

Your explanation is really good. You must have spent too much time figuring out this much. I know because I am trying this for laminated composite. Can you help me get the results? I am not able to get results. The job is getting aborted. Or can you put some video for laminated composite DCB(Double cantilever beam) test?

Hi Dithoae ,I want to know why there is no Possion’s Ratio, Thank you much!

@Jdjfbrjjjhdhbb

6 жыл бұрын

For glue

@user-mu5zu4nd3k

6 жыл бұрын

bacause it is cohesive element.parameters determined by traction-separation law.

@Jdjfbrjjjhdhbb

6 жыл бұрын

一只胖猫 多谢🙏

SIR, how to provide slip property between reinforcement and beam. I am using surface to surface contact and provide normal, tangential behaviour (friction coefficient=.45) I hole in my beam and insert reinforcement as solid element but it doesn't take any attempt. sir any suggestion to how to provide slip property between reinforcement and concrete.

@FEADith

4 жыл бұрын

Hi Can you be more specific on the slip properties? what do you mean with slip properties..?

@navdeetsaini253

4 жыл бұрын

@@FEADith Sir I am b. Tech civil engineering student(INDIA) Sir, I try to give slip property between steel reinforcement and concrete beam. Sir generally we draw reinforcement as wire element and embedded into solid beam element. but practically no reinforcement is fully embedded therefore I try to give slip property using cohesive surface and provide friction coefficient but there is some convergence problem.

@navdeetsaini253

4 жыл бұрын

@@FEADith sir if you have time then i am hard to send y abaqus file to you

@FEADith

4 жыл бұрын

@@navdeetsaini253 hi I am sorry i cannot help you to see your problem in more details. But if what you want is to explicitly model steel column inside the concrete beam.. you might want to use merge cut operations (such as in this video kzread.info/dash/bejne/k2mpq7Btg9vQaMY.html ) and assign sliding properties as in this video kzread.info/dash/bejne/iat-0qOeZ5awpqg.html hope this helps

THANK YOU, YOU ARE VERY HELPFUL, BUT YOUR MOUSE NEED SOME LUBRICANT! JUST JOKING!!! :)

I followed all the steps from the video and run the simulation. After a moment, I got an error "TOO many increments needed to complete the step." could you help me?

@BulletManiac666

6 жыл бұрын

Hello, I have the same problem. Did you find the solution to this???

@drake7344

6 жыл бұрын

go to edit step, incrementation, and increase the maximum number of increments?

Why should we use type=traction for cohesive element? Why not isotropic?

@FEADith

4 жыл бұрын

Traction type means that you have traction separation relationship. So you multiply the stiffness matrix and the separation between 2 faces. While if you use isotropic, they will expect strain instead of separation. But go ahead and try yourself. Maybe it works

Is it possible to simulate two CZM in single model?

@FEADith

4 жыл бұрын

Yes its possible.. just make 2 elemnts sets and assign to different cohesive materials

@chetanhc5495

4 жыл бұрын

@@FEADith thank u

If u put subtitle you'll help lots of people

Hi, How can i get cohesive material properties of material like fracture energy, nominal stress

@FEADith

6 жыл бұрын

B. Vipul you can do basic test like DCB test for mode 1 frature energy, ENF test for mode 2 fracture energy or MMB test for mixed mode fracture energy

@WorldinFocus360

6 жыл бұрын

Thanks for your reply, can we get these information using nano-indentation

@FEADith

6 жыл бұрын

B. Vipul i dont think you can get it from nano indentation. Usually from nanoindentation, you may get hardness (related to plasticity) and Young's modulus.. but not the fracture behavior.