Example 3.5 How to use Abaqus to model a ply drop off, terminating laminas one by one

[@mdasifrezwanshishir742]

Hello Dr Barbero, thank you for your videos demonstrating the examples of your book. It really helps to understand the steps why we are doing this instead of just clicking on different options. I just wanted to ask you, for a type of reinforced foam core composite, what are the ways to get the orthotopic properties or engineering constants such as; E1-E3, nu11~23, G11, G12 etc? I could not find any journal papers where these are stated so I am bit stuck modeling them in ABAQUS

[@EverBarbero]

I share your frustration with the lack of data, but for the core the only elastic properties that matter are G13 and G23. All other E's, G's, and nu's you can put small numbers as long as they do not trigger an error--see "restriction on elastic properties" in my book. The effect of all other properties is dominated by the properties of the skins. For G13 and G23 you can do a separate 3D model of an RVE of the core, using shells for the walls of the honeycomb, of solids for a foam, then chapter 6: computational micromechanics, to get the properties G13 and G23 in terms of the properties of the honeycomb paper, or foam properties.

[@EverBarbero]

In addition to my earlier response, please see Ex-3-7-a, b, c, and d.

[@mdasifrezwanshishir742]

@@EverBarbero Thank you so much Dr. Barbero! I really cannot express my gratitude in words for your well-detailed explanation. I understand now what I have to do. I just hope it aligns with the restrictions of ABAQUS. I will follow up with your suggestions and if it works, I will give you feedback later on. Thank you again! :)

[@mahaelsaeid3713]

hello Dr. Barbero , thank you for the useful video, I was wondering if the ply drop off method can be used to simulate defects like gaps( not gradual gaps, a sudden messing tape in some plies) ? also I have a question in the video, can we model the part using sole deformable extrusion instead of shell planar ? also why did we put edge semmitry boundary condition in the y axes ?

[@turanturan2831]

Prof. Barbero, I did not get why it bends toward the Z-axis? This load is something like tension, right? Is it the effect of B matrix (load-curvature coupling)?

[@EverBarbero]

Yes, due to B of the laminates is part of the reason for bending but more so is the offset between the middle surface of some sections and the plane where the load is applied. To get my email address go to kzbin.infoabout

[@taktahuke]

great video sir. One question, how did you do validation for the example ?

[@EverBarbero]

I didn't. The way it works is you validate the software--Abaqus in this case, specifically for the type of element you are using--with examples for which there is experimental data or analytical solutions, and if that is lacking with solutions from other software, and once you are satisfied, you trust the software.

[@taktahuke]

@@EverBarbero Thank you sir for the reply :)