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Dear friends,

I have a a severe problem about defining a damage criteria for commercially pure Aluminum to simulate its machining process by Abaqus. I will please if you solve my problem by intriducing a practical damage criteria for this case. I am looking forward to hearing from you.

Your sincerely,

Cina Qabchi.

Hello,

I would like to know how contact elements are different from " general "ie non contact finite elements.

Also I would like to know how Lagrange multiplier method is used in contcat analysis.

My understanding of the Lagrange multiplier is like this: when we have to impose a constraint equation

[C][D]=[Q] as constraint between DOFs, we incude a term Y*{[[C][D]-[Q]} where Y is the Lagrange multiplier ,in the potential energy functional and minimize the functional  to get the algebraic equations.

When I run my subroutine,  I get a error that is

***ERROR: in keyword *EQUATION, file "Job-1.inp", line 973: The keyword is

           misplaced. It can be suboption for the following

           keyword(s)/level(s): assembly, instance, part

does anybody know aboutthe Keyword *Equation? andthe following is my inputfile I dont know whats wrong with it?

Dear all 

i am a new abaqus user, now i use this software to modeling a few layers of soil layers (in geotechnical engineering), here is the information of the ground profile

[0-4m] fill sand layer; Density = 18kN/m2, firction angle=30, cohesion=0, void ratio=0.5  

[4-12m] marine deposit; Density = 16kN/m2, firction angle=10, cohesion=30, void ratio=0.5   

[12-22m]  Alluvium; Density = 18kN/m2, firction angle=30, cohesion=5, void ratio=0.5   

Hello,

i'm working on the modeling of thin plate under transverse load. The basic function used for approximation of field variable is RBF function. There are a lot of publications, how the static model of the plate can be created, but no information about dynamic modeling. The following questions are not clear for me:

I used *Coupling to make sure the one-direction displacements Ui of the nodes on the same plane are the same, but the question is the reference node can not be localized on the plane so that I dont know which reference node to choose near the plane. Additionally, even I choosed a node closed to the plane , the Ui of the nodes on the plane are different, who can explain this problem? Thank you so much!

Hello everyone,

I need to create a semi-elliptical surface crack in a cylinder using ANSYS. CTMOPT macro allows modeling and meshing of this type of crack, but I am struggling to get this. If anyone knows detailed information regarding this, kindly let me know.

Thanking you,

Ashish Joshi