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modeling adhesive in ANSYS


i am studying adhesive joints of sandwich panel.I used contact elemet in  ANSYS software to modeling adhesive but my solution did not converge.I used smaller elements and increased the number of susteps, but they could not help me. do you know what the problem is?

thanks in advance,

Best Regards

Aidin Ghaznavi

problem related with full integration


I am new to ABAQUS and have met a problem in input file. If I set the element type to be CPE4R, the input file works perfectly. However, CPE4R has only one integration point, which is not enough for my problem. When I define the elment to be CPE4 in the input file and set section control to be hourglass, the computation is terminated with error in input file. I don't konw what's the problem here. Could anyone help me with the problem?

Any information is appreciated.


Can I input variable piezoelectric properties to UMAT subroutine and do coupled piezoelectric analysis?


 I am using abaqus to do research on polarization procedure of piezoelectric materials. I want to develop a user subroutine that can allow me to input variable piezoeletric material properties and do coupled problem. I want to know if UMAT can solve this problem or I need to use other subroutine. If there is that subroutine, what is it.  Any suggestion is appreciated.

 Thanks in advance,

Linhui Zhang

Modeling Reinforced Concrete Element in Abaqus Standard

hello everyone,

I am trying to model a concrete element subjected to static load using Abaqus Standard. For concrete, I am using Concrete Damaged Plasticity and beam elements for my reinforcement. I am embedding my reinforcement into the concrete (host elements).

Since I started, I faced several issues. They are overconstraint, numerical singularity and negative eigen values. I managed to resolve both of them. However, the behavior from my model is nowhere near the experimental data that I have. It seems that the model is excessively stiff.

free vibration mode shapes of beam (other than pinned-pinned) and finite strip method

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Hi everyone.

I'm working on my master thesis, dynamic analysis of plates using finite strip method.

I have found one problem (among others) that could be interesting to community.

In the attachment you can find example from Mathematica. There is 21 mode shapes of clamped-clamped beam. Recently i noticed that formulation given in every book about dynamics (Timoshenko, for example) isn't valid for higher modes for any beam that isn't pinned on both ends.

Marino Arroyo's picture

Postdoc positions in Barcelona: modeling and simulation in biophysics

We have several postdoctoral positions open, funded by an European Research Council Starting Grant. We look for candidates with a PhD in Engineering, Physics, Chemistry, or
Applied/Computational Mathematics. In addition to excellent communication skills, initiative and an inclination for inter-disciplinary research, experience or interest in preferably more than two of the following areas is required:

  1. Computer simulations (continuum and/or atomistic methods), programming

Bridging the gap with a "stepping stone" for more solar energy

Converting the abundant energy from the sun into a form convenient for human use has been a long standing dream for sustainable generation of environmentally clean energy.  With the seminal discovery of water splitting by Fujishima and Honda in the early 1970s [1], titanium dioxide (TiO2), an inexpensive white pigment widely used in our daily life, emerged as the premier photocatalysts for enabling solar energy utilization. However, because of its wide intrinsic band gap, TiO2 can absorb only ultraviolet light. This results in less than 1% efficiency for solar energy conversion. Reducing the band gap of TiO2 is the main avenue for boosting the conversion efficiency. In a recent paper to appear in Phys Rev. Lett. [2], Zhu et

Dr. Michael Nosonovsky's picture

Green Tribology

Tribology is defined as the science and technology of interacting surfaces in relative motion, which involves friction, wear and lubrication.

The term “tribology” was introduced in the 1960s by Prof. Peter Jost.  In the consequent decades, various aspects of interacting surfaces in relative motion have been the focus of tribology, including, for example, the tribology of automotive applications, microelectromechanical systems, magnetic storage devices, adhesive contact, micro/nanotribology, biotribology.

Tenure-track Assistant Professor postion in Engineering Mechanics at the University of Texas at Austin

The Department of Aerospace Engineering and Engineering Mechanics at the University of Texas at Austin has a tenure-track position at the Assistant Professor level beginning September 2010 in the area of Mechanics of Solids, Structures and Materials.

Contact Analysis using Abaqus 6.9

Dear All

 Currently I am working as a researcher and there is a new project on which i need some help. I have to do a contact analysis between two bodies initially and than move to low speed impact betrween two composite materials. I have just started using Abaqus and not very familiar with it. I have although completed some very basic application like cantilver beam and stress analysis, but struggling to complete a contact analysis between two bodies in a simple 2D problem.

Speech of Acceptance of the 2009 Timoshenko Medal by Zdeněk P. Bažant^1

Zdeněk Bažant

ASME International Mechanical Engineering Congress
Orlando, Florida, November 17, 2009

Reminiscences and Reflections of a Mechanician by Luck

Mr. Chairman, Ladies and Gentlemen:

Nanoscale Computation/Modeling Domain Expert Opening at Lurie Nanofabrication Facility

The Lurie Nanofabrication Facility (LNF) is the University of Michigan site of the National Nanotechnology Infrastructure Network (NNIN) and is hiring a new domain expert in computation and modeling.

Henry Tan's picture

Impact of cellular materials

As the title suggests, there are two focuses of this discussion theme: impact and cellular materials.

Impact protection can be very practical problems in safety, fires and explosions, oil and gas industry, subsea structures, car manufacturing, nuclear industry, rocket space engineering, etc.

Venkat Bharath's picture

Cohesive behaviour for Interaction in Abaqus Explicit at the interface of materials

I am working on effects of Blast Loading in sandwich composites using Abaqus. I want to incorporate Cohesive behaviour at the interface of the two materials in the sandwich composite structure i am analysing.

crack initiation simulation with FEM

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i want to simulate the the crack initiation, but i don't know

(1)what criterion should i use for crack initiation.

(2)how to deal with the mesh(unlike other fracture model, there is no crack defined in advance in the mesh).

the material i use is structual steels.


 could anyone give me some advice?


best regards


GOPALAERO2000's picture

Effect of surface hardness in tensile testing

Hi Everyone,

 Is is possible to account the surface hardness effect in the tensile testing specimen? If possible, how could it be acomplished?

For instance, I would like to establish the  stress strain curve for the material that used on surface hardened component. Will there be a big change if the surface hardness effect is considered on the tensile specimen?


Please throw some light in this regard.



M Gopalakrishnan

Abaqus Standard: Overconstraints & Negative Eigenvalues

hi, i am using Abaqus standard to model a reinforced beam-column connection subjected to a tip load at the end of the beam. 

i first applied a gravity load followed by a tip load at the end of the beam. halfway through the application of the tip load, abaqus standard
stop and give 2 errors.

1) overstraint at certain nodes of my longitudinal reinforcement

2) negative eigen values

T.ZENG's picture

Viscoplastic OR elasto-viscoplastic simulation

When reading papers about visco-plastic or elasto-viscoplastic simulation, all authors only say that the orientation of grain used in the simulation can be randomly generated, and does not refer to how to generate them. I know the orientation of grain can be expressed by Euler angles (phi1, ph, phi2), but can someone give me advice how to generate euler angles?

Muthukumar M's picture

How do find Inverse to Rectangular Matrix?

Dear All,

How do find the inverse of the rectangular matrix.

Harold S. Park's picture

Tenure-Track Positions in (1) Solid Mechanics and (2) Bioengineering at the University of Colorado

The Department of Mechanical Engineering at the University of Colorado
at Boulder invites applications for two full-time positions beginning
fall 2010. The positions are for tenure-track assistant professors with
disciplinary expertise in the areas of (1) Bioengineering (posting #808181), and (2) Solid Mechanics/Materials Physics (posting #808182);
higher rank may be considered for experienced candidates. Candidates
are expected to strongly complement and strengthen existing
departmental research in biomechanical/biomaterials engineering, energy
and environmental engineering, micro/nanosystems engineering, materials
engineering or solid/fluid mechanics. Candidates must have an earned

Srikar Vengallatore's picture

Workshop on Microactuators and Micromechanisms, Aachen, Germany (May 27 - 29, 2010)

This workshop is being organized under the auspices of the International Federation for the Promotion of Mechanism and Machine Science (IFToMM).

Topics of interest include: Microactuators, Microsensors, Micro-opto-mechanical devices, Mechanical Tools for cell and tissue studies, Micromanipulation, Micro-assembly, Microscale flight and swimming, Surgical tools, Micro-robotics, Micro-scale power generation, and Miniature manufacturing machines.

Please consult the Call for Papers (attached) for further details.


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