Mode I crack of the glued timber by cohesive behavior interaction

Modeling of the mode I crack of the glued timber using the cohesive behavior from my Ph.D. thesis.

[@vandangtran6454]

Mode I crack propagation of the glued timber bar by using the cohesive behavior interaction on Abaqus

[@hazemismaeel1488]

Hi Sir how to get an electronic copy of your thesis

[@vandangtran6454]

you can follow this link: www.researchgate.net/publication/266148615_Experimental_and_numerical_analyses_of_the_structural_response_of_adhesively_reconstituted_beech_timber_beams

[@suvarnav6742]

Sir was modelling the debonding of DCB specimen where the adherents are CFRP and Al , I followed the same steps to define cohesive interaction but no debonding is taking place? please help!

[@vandangtran6454]

@@suvarnav6742 may you have to well define the parameter of cohesive interaction? you can reduce the values of parameters for comparison

[@erfanroghani5273]

it's very good that you mentioned the article in the video thanks.

[@vandangtran6454]

You're welcome

[@houmanganjali8397]

Dear Dr. Dang, Many thanks for the informative video, but I have a question. The result of the final Figure in the video above(18:34) is supposed to be similar to Fig .10, FE model(the blue line) of your paper, but X axis(displacement) is not identical, although Y axis and its values are same as the ones in the video. why is that?

[@Bistaolee]

Thank you for this vidéo i have à question which curve we can plot in this simulation exept force-displacement ????

[@henrimonette5399]

Thank you for this very informative video. I myself am modeling bolted connections in glulam elements. I am trying to use cohesive behavior to capture mode I and mode II cracking. I was wondering, how would you suggest calculating the Knn, Kss, and Ktt? My first thought was to use the elastic modulus of wood perpendicular to the grain and shear modulus in the corresponding direction, respectively. Would that be appropriate? If not, how do you suggest calculating these parameters? Thanks a lot for your time!

[@vandangtran6454]

Hello, What I did was to carry out mode I and mode II cracking tests, then simulated these tests in Abaqus, compare the results of the model with the experiment, vary the values of the traction-separation model (K, sigma, final displacement) until the comparison was consistent, and obtain these values.

[@iman471]

Dear Dr. Van, Is it possible to model the crack using SEAM option in ABAQUS? I want to model the beam-to-beam connection using compressed wood and dowels. exprimental study indicated that the carck developed in dowels and timber and connection plate. it is so difficult to use cohesive element in this complicated model. can i model that using SEAM?

[@CHANNEL-cf2oh]

Hi sir thank you very much for this tutorial. Sir I am beginner, and I need to use abaqus to model a traditional timber structure, what kind of parameters do I need to include in my model.

[@vandangtran6454]

Timber should be defined as an anisotropic material with brutal damage in tension and ductile damage in compression. So, for the elastic term, the type of Engineering constants must be used. for the plastic term, the isotropic hardening is used to get. Hill criterion or Hoffman criterion is used for the damage simulation of timber. Good learning!

[@killianonwudiwe5321]

Dear Dr. Tran, Please I am trying to do similar simulation using a cohesive zone element. I have tried replicating your model and the deformation, just t have a grasp of how I can do same for my work. But I keep having issues with increment size. I was hoping you can help me figure out where I am not doing t right

[@vandangtran6454]

Hi Killian, I used the "cohesive surface" in this example. if you use a "cohesive element", you should create a part as the cohesive part, then define it as a cohesive matérial. note that the mesh type "cohesive" has to be made for the cohesive part. I hope that meets your question.

[@killianonwudiwe5321]

@@vandangtran6454 I dont know if you are free to answer some of my other questions. Can we talk on skype or somewhere else?

[@vandangtran6454]

@@killianonwudiwe5321 send me your problem via mail: [e-mail]

[@killianonwudiwe5321]

Ok I will thanks alot

[@yanamycugy]

Hi anh, em đang làm bái toán liên quan đến phần tương tác cohesive này, trong đó phần định nghĩa damage evolution em có thử dùng thông số total/plastic displacement, em thử định nghĩa nó bằng tỷ số của các chuyển vị chia cho chuyển vị tại ứng suất đỉnh, tuy nhiên kết quả không khả quan lắm, em có tìm hiểu thì không thấy nhiều tài liệu nói đến thông số này, anh có thể giải thích giúp em được không ạ, em xin cảm ơn

[@vandangtran6454]

Hi em, giá trị này hiểu là phần chuyển vị dẻo khi phần tử hoàn toàn bị phá hoại. Nhấn mạnh là nó là giá trị của phần tử "element", nên không thể tính từ đường cong thực nghiệm được. Nó phụ thuộc vào kích thước phần tử của mỗi model, nên dùng phương pháp thử dần, cho đến khi đường cong model và thực nghiệm khớp, và tìm ra giá trị đó. good luck :)

[@choustephen461]

Dear Dr. Dang, i've watched your simulation, it so interesting and useful for me to simulation using cohesive element. My material is composite, i'm simulating with Mode - I, a thickness of cohesive interface not equal zero ( not like you), and it palced between 2 composite layer. So how i can make constrain between composite and cohesive interface (in interaction modul, abaqus)???

[@choustephen461]

By the way, i you can, please give some references like some example for simulation cohesive.

[@vandangtran6454]

With your case, we can say "cohesive element", that means you must to define the cohesive as a normal material with mechanical parameters. Then, between the composites and the cohesive interface, a constraint type of "tie" may be used for the connection.

[@saroj4736]

can you help the same with ansys?

[@hardikzadafiya729]

Hello Van i am engineering Student. I am doing my research on masonry wall in abaqus. i am literally stuck with interface and interaction. If you guide me how to do that is very helpful me. i also read to many research papers but i can't understand much. Can help me please?

[@vandangtran6454]

it will be a pleasure to discuss with you

[@tranphong2948]

chào bạn, mình đang nghiên cứu về vật liệu gỗ dị hướng, mình mô hình một liên kết chốt trong gỗ LVL, nhưng khi chạy sơ đồ abaqus báo lỗi. mình cũng thao tác khai báo vật liệu như video của bạn mà chưa tìm ra nguyên nhân. Rất mong được giúp đỡ. Cảm ơn bạn. "Error in job Jobtet: Anisotropic material properties without a local orientation system have been defined for 2912 elements. Anisotropic material properties must be defined in a local orientation system. The elements are identified in element set ErrElemAnisotropicMaterial. Job Jobtet: Analysis Input File Processor aborted due to errors."

[@vandangtran6454]

Đối với vật liệu anisotropic, sau khi gán vật liệu xong bạn cần gán hướng vật liệu, nghĩa là định nghĩa các hướng 1,2,3 cho part, trong (part/orientations)

[@lakhdaramraoui]

I need how to create a Fracture mod1 in a beam using ansys apdl

[@vandangtran6454]

Sorry, i dont know how to work in ansys

[@iman471]

Dear Dr. Van, Is it possible to model the crack using SEAM option in ABAQUS? I want to model the beam-to-beam connection using compressed wood and dowels. experimental study indicated that the crack developed in dowels and timber and connection plate. it is so difficult to use cohesive element in this complicated model. can i model that using SEAM?

[@vandangtran6454]

The crack developed in timber may be simulated using a supposed fracture. it means that you should separate the real timber part in 2 virtual part with the boundary between being the same place to the fracture. Then, the cohesive surface with traction-separation law is used for the simulation of the fracture of timber. Good luck!