User login


I am trying to simulate Cyclic Loading in ABAQUS, there by trying to estimate the Fatigue Life of an Automobile Recliner subjected to 25000 cycles. My questions are1. Is it possible to apply Cyclic Loading in ABAQUS?2. Feasibility of Fatigue Analysis in ABAQUS? Bharath PProject TraineeIFB APL, BangaloreKarnataka, India

yawlou's picture

Help regarding 2D co-rotational beam formulation

I have implemented a 2D co-rotational truss formulation in matlab.  I get identical results to OpenSEES.

Now I'm trying to implement a 2D co-rotational beam formulation.  I have followed the simple formulation in Crisfield's book volume 1.  It seems like this should be a fairly straight forward extension of the truss formulation.  I have rederived everything Crisfield has done and obtained the same results, yet something is still incorrect.

Zhigang Suo's picture

Free Energy

For a system in thermal contact with the rest of the world, we have described three quantities: entropy, energy, and temperature. We have also described the idea of a constraint internal to the system, and associated this constraint to an internal variable.

Mike Ciavarella's picture

Strain gradient plasticity: the flow rule of Fleck and Hutchinson violates thermodynamics ?

A recent paper on JMPS has seriously questioned the foundation of the SGP theory of Fleck and Hutchinson.  The matter is not simple, but is it a good bench test for imechanica to discuss?


Boat simulation-how to define the buoyancy? Can it be done in ABAQUS

I am trying to model a boat sitting in the water. I want to see the stress distribution after the boat is put in the water. If I only consider the solid boat model, I need define the weight of the boat and the buoyance otherwise the boat would not be in a equilibrium. My question is that how can I define the buoyance in ABAQUS, or I have to find an alternative to define the floating force? Since the water pressure is function of depth, I think we might be able to define the pressure at different level. But I don't know if it will works fine.Any comment will be appreciated.Thanks a lot.

Call for Abstracts - Symposium on Advanced Computational Methods for Fracture (IMECE 2009)

This is topic 12-21 Advanced Computational Methods for Fracture in the upcoming ASME Congress 2009 (November 13-19, Lake Buena Vista, FL., USA.) Deadline for abstract submissio: March 2, 2009.

The aim of the topic is to recognize the recent development in the computational tools for fracture characterization. The topic is open to all contributions on numerical techniques, simulations of fracture problems at all length scales, failure mechanism modeling, fracture prediction, and computational algorithms to achieve these goals.

Zhigang Suo's picture

Evolving small structures

I taught this course at the University of California, Santa Barbara, in Winter 1994, Winter 1995, Spring 1996; at Princeton, Spring 2003; at Harvard, Spring 2004.  The notes posted here are those distributed to the class in Spring 2004.


T.ZENG's picture

Solve Navier type function with Green Function and Fourier Transformation

I am a freshman in micromechanics area. Many books and papers always say the linear elastic equilibrium equation(Someone also called Navier type function) could be solved with Green Function and Fourier Transformation, but without details. May be the writers think anyone should know these two popular methods in solving the PDE. I have search many books(both mathmatic and mechanics), However, there are little information about solving the navier type function with those two methods. 

Zhigang Suo's picture

How does temperature become a number

An essential step to “understand” thermodynamics is to get to know temperature: how temperature comes down as an abstraction from empirical observations, and how it rises up as a consequence of the fundamental postulate.  I have just updated my notes on temperature.  The beginning paragraphs of the notes abstract temperature from empirical observations.  These paragraphs are posted here.

Fifth MPM Workshop, Corvallis, April 2-3, 2009

From Prof. John Nairn:

Dear Colleagues,

I am writing to see if we can arrange the Fifth MPM Workshop to be held
at Oregon State University (Corvallis, OR) April 2 & 3, 2009.
Please respond soon (since time is getting short) with following items:

1. Attendence
    a. I will plan on attending
    b. I will try to attend if possible
    c. I cannot make it
    d. I could make a different date (this date was from a mini poll)

T.ZENG's picture

Why always warning Comment field is required

I want to reply to other people's comment , but when I finish the reply and clikc the "post comment" it always warns comment field is required , I Do not know what is wrong. If someone knows the problem, please tell me, thank you very much!!!

Ajit R. Jadhav's picture

Java for High-Performance Computational Engg. / Sciences?

In the past few days at iMechanica, there have been quite a few messages dealing with different aspects of programming, libraries and so on...

It would perhaps be timely, therefore, to ask:

Do you have any opinion about using Java in numerical analysis (NA) / FEM / CFD etc.---i.e., in computational engineering and sciences (CES)?

Do you have any experience or hard data concerning performance of Java vis-a-vis C++ or FORTRAN, esp. for large systems, or for high-performance applications? Any pointers?

modelling of cohesive zone in Ansys

Dear Friends,

 I try to make simple model of crack propagation in Ansys but cannot get the clue what i dont include in programming file that I cannot see the propagation of crack, the cohesive layer doesnt break, simply stretching like rubber. Could somebody to give me advice on this topic?

thank you!


Alejandro Ortiz-Bernardin's picture

Near-incompressible analysis

Hello all,

I am studying some simple finite elements for 2d near-incompressible analysis. Particularly, I am interested in the MINI element. It is basically a 3-node triangle element with nodal pressure and displacement degree of freedoms enriched by a bubble function. Could someone that has some experience with these elements point me out about advantages and drawbacks of using these type of elements?



T.ZENG's picture

Self-consistent Modeling of plastic and viscoplastic polycrystalline materials

I am a freshman of researching the macro response of  metals with micromechanics scheme. Now,I have to build a  self-consistent modeling of plastic and viscoplastic for polycrystalline materials. However, it seems difficult for me as I have little knowledge of polycrystalline and its mechanics propertities.

If you know some systematic books or papers about my research area. please let me know. Your kindness will be great appreciated!!!

What yield criterion must I use?

Choose a channel featured in the header of iMechanica: 

Nowadays I am analyzing a study of a hip prosthesis including the bone. I am making the FEA/FEM analysis by Pro/Mechanica software. Metallics materials are titanium alloy (Ti-6Al-4V) and Chromium-cobalt-molybdenum alloy (CoCr29Mo). So they are ductile materials. I understand the main load is the flexural load on the hip.

Compressive strength/failure test on brick

Choose a channel featured in the header of iMechanica: 
Free Tags: 

Hi everyone. I'm new to this forum and quite new with FEA.

Currently i'm trying to find compressive strength or maximum failure stress on a modeled brick. Is't possible? What parameters or properties do i need in hand in order to proceed?


concrete damage plasticity model in abaqus

I am doing plain concrete beam subjected to low velocity impact model in abaqus. for model the concrete i have choosen concrete damaged plasticity. Is it the proper selection for model the concrete under dynamic loading. If it is correct, how to get the tensile behaviour of concrete (yiled stress, cracking starin) from uniaxial test data (yiled stress, inelastic strain). Please help me if any body is having the idea on this.

Glasgow: 4-year Post-doc XFEM for 3D crack growth with goal-oriented error estimation including industrial applications

University of Glasgow, Civil Engineering, Mechanics and Materials

Increased Reliability for Industrially Relevant Automatic Crack Growth Simulation with the eXtended Finite Element Method (Funding for £483k)

A unique EPSRC funded 4 year post-doc to investigate

- goal-oriented error estimation in XFEM

- adaptivity for 3D crack growth

Xi Chen's picture

ASME IMECE2009 Symposium on Multifunctional Material Systems

The ASME Multifunctional Materials Technical Committee of the Materials Division is organizing a symposium on Multifunctional Material Systems at IMECE2009 to be held in Lake Buena Vista, FL, during Nov. 13-19, 2009.

Abstract submission deadline: March 2, 2009

2D approximation of heterogeneous 3D media

Dear All,

Could somebody indicate me some literature about the topic "2D
approximation of heterogeneous 3D media"?

In particular I am interested to address following issues:

1) Under which conditions averaging thermal conductivity and young
modulus (or more general, mechanical behaviour) on multiple 2D crossections of an heterogeneous "random"
material can be a good approximation for the behaviour of the real 3D


Subscribe to iMechanica RSS Subscribe to iMechanica - All comments

Recent comments

More comments


Subscribe to Syndicate