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navidtajik's picture

speckle pattern interferometry/stress measurment method

I’m working on optical method for displacement measurement. and this is interesting to know more about application and development of these methods like ESPI , SHEAROGRAPHY anf HOLOGRAPHY . for example i face with a company that climb their product can give displacement and so strain field in many material and many geometry even in 3-D shapes!!

http://www.dantecdynamics.com/Default.aspx?ID=1029 

Jianliang Xiao's picture

Mechanics of in-surface buckling of one dimensional nanomaterials on elastomeric substrates

In this recently published paper on Nanotechnology, we studied the in-surface buckling mechanics of one dimensional nanomaterials on elastomeric substrates.  Simple analytical solutions are obtained for buckling wavelength and amplitude, which can be easily applied to the in-surface buckling of different nanomaterials, such as nanowires and nanotubes.  It is shown that in-surface buckling of nanomaterials has lower energy than out-of-surface buckling, which explains the experimental observance of

HCHan's picture

Postdoc position in vascular mechanics

The Cardiovascular Biomechanics Lab in the Department of Mechanical Engineering at The University of Texas at San Antonio (UTSA) is seeking a highly motivated postdoctoral fellow to join our research team. The position is supported by a research grant from the NIH to study the mechanical stability and tortuosity of blood vessels. Qualifications include a doctoral degree in BME or ME in computational fluid mechanics, or computational biomechanics.

Integrity of Scholarly Publishing under Attack

 

This issue of CAM digest re-published D.N. Arnold's article  "Integrity under Attack - the state of scholarly publishing". The orginal article is available via weblink

http://www.ima.umn.edu/~arnold/siam-columns/integrity-under-attack.pdf

Zhigang Suo's picture

Stress Corrosion

A glass may withstand a static load for a long time (days, weeks, or years) and then, without warning, breaks suddenly. Here are salient empirical observations:

whyakhan's picture

thermal radiation analysis in ansys workbench 12

Hello everybody,

I have been assigned the task of performing thermal analysis of electronic components that involve conduction and radiation only and determine the temperature distribution on them. I am doing this in ansys workbench 12. Since I am doing thermal analysis for the first time so having problems.

Does anybody have tutorials related to performing thermal analysis in ansys workbench. Please share.

Thanks in advance.

Regards,

Muhammad Yousuf Ayub

Qing Xiang PEI's picture

Postdoctoral Research Associate Position at IHPC of Singapore

We are seeking outstanding candidates for a Postdoctoral Research Associate Position at the Institute of High Performance Computing, Singapore. The position requires a Ph.D degree in physics, chemistry, materials science, chemical engineering, mechanical engineering or equivalent experience.

Additional requirements include:

. Knowledge in mechanics of materials

Rui Huang's picture

Effects of mismatch strain and substrate surface corrugation on morphology of supported monolayer graphene

In a previous work, substrate-modulated morphology of graphene was analyzed using a numerical Monte Carlo method. Here we present an analytical approach that explicitly relates the van der Waals interaction energy to the surface corrugation and the interfacial properties. Moreover, the effect of mismatch strain is considered, which predicts a strain-induced instability under a compressive strain and reduced corrugation under a tensile strain.

Henry Tan's picture

Subsea Integrity

I am teaching Subsea Integrity for the MSc students majoring in Subsea Engineering at the School of Engineering, University of Aberdeen. This is a course that combines the fundamental principles (corrosion, fracture, fatigue and material selection) with the industry applications (subsea integrity management and implementation, cathodic protection, case studies on subsea reliability and engineering assurance).

 

Teaching time schedule

Zhigang Suo's picture

Fatigue

These notes were prepared when I taught fracture mechanics in 2010, and were updated when I taught the course again in 2014.

Notes on other parts of the course are also online.

 

question about Gurson model

I have a question regarding Gurson model. If we have a cube with initial length of unit and initial porosity of 20 percent and compress it hydrostatically in order to have a huge volume change of cube, the void growth equation in Gurson model takes a negative rate and reduces the void volume fraction to zero first and further compressing leads to no further void volume fraction change (remains zero) and no more plastic straining. Now let's load the model in tensile hydrostatic state up to a stress free configuration; the void volume fraction of the model remains zero.

Hirschberger's picture

Position for Research staff member at Leibniz Universität Hannover, Germany

The Graduate School MUSIC ("Multiscale Methods for Interface Coupling") and the
Institute of Continuum Mechanics at Leibniz Universität Hannover invites
applications for a position as a

Research Staff Member in Computational Mechanics

(Salary scale E13 TV-L)

to be appointed on 1 April 2010.

The position is embedded into the Junior Research Group on „Multiscale Modelling of
Materials and Interfaces with Size Effec
ts” and is initially limited to 1 year.

Thermal stresses from pre-defined temperature data (thermography image)

I´m facing a problem in which a I´d like to assess stresses due to thermal gradients. I have an IR thermography image (recorded as a matrix) and I like to introduce those temperatures to Abaqus via Matlab.

Is that possible? Or should I use FORTRAN with the UTEMP subroutine?

Thanks in advance,

 

Aitor  

Soil Modeling

Hi

Please help in modeling the soil.

I  modelled soil as non linear springs in Abaqus?Standarads and analysed the pipe behavior for hydrodynamic loading.

I am currently planned to model the pipe-soil interaction with soil as an 2D or 3D element along with contact properties. Give me suggestion or methods how can i model soil.Suggested reading materials.I have gone through the abaqus documentation.It tell that soil can be modeled as 2D or 3D.I am really confused which one to use. 

Please give me some steps in creating soil and pipe model .

 

Effect of the interfacial stress distribution on the material interfacial shear strength measurement

The interfacial strength is a very important material property for composite materials and other hybrid materials with different stress distributions. Will the interfacial stress distribution have a significant effect on the interfacial strength measurement?

Schematic of short-beam test with Iosipescu fixture

 Comparison between experimental and simulated fringe patterns

Zhiqiang Wang's picture

PhD position available in computational multiscale modeling of engineering materials

A PhD position is available in the area of computational multiscale modeling of engineering materials in the Department of Materials Science and Engineering in the College of Engineering at University of North Texas (UNT). Financial support will be provided through research assistantship. The student will participate in research activities to study material defects, microstructure evolution, and mechanical behavior of crystalline metals, alloys, and nano-composites for a wide range of important applications in areas such as energy and aerospace.

another practical optimization problem (IOSO vs Genetic Algorithm)

Dear Colleagues,

Let us continue viewing the efficiency of the application of various optimization methods on practical optimization problems.

 

Why we start from honeycombs rather than cocoons.

The study of cellular solids is greatly influenced by the honeycomb. However, the honeycomb is not a component as whole for bees. Instead, the bee only care the shape and mechanical property of the cells, but in the engineering field, a cell of honeycomb is seldom used. We use them as plate, shell and so on. I think we ignore another porous material called cocoons, the protection to the most fragile period of insects. It is always bearing the load as a whole component.

Gregory M. Odegard's picture

Newsletter for the ASME Committee on Constitutive Equations - Spring 2010

Mechanics community,

Please find attached the spring 2010 edition of the ASME Committee on Constitutive Equations Newsletter. Included in the newsletter are short articles on "Constitutive Modeling of Skeletal Muscle Tissue" and "Nonlocal Modeling of Materials".

Thanks,

Greg Odegard

Abaqus, element removal

Hi everybody,

 is there anyone who is familiar with element deletion or removal to predict crackopening in RC member model in ABAQUS?

I've made a 2D model of RC beam in abaquse with brittle cack properties and brittle failure but I could not get any result. Can I make my model by concrete damage plasticity and using abaqus standard to apply element removal?

I will really appreciate anyone who helps me to solve my problem.

 Thanks in advance

venapa's picture

Dynamics of AFM cantilevers

Hi everyone,

I am looking for papers on the dynamics of AFM cantilevers in contact with non linear material samples. In particular, I am interested in forced armonic vibrations of the catinlevers.

I have seen many papers on intermittent contact (or tapping) which has a number of additional problems w.r.t. the contact mode.

Many thanks for the help.

Pasquale V.

SivaSrinivasKolukula's picture

Accelograms.......

Choose a channel featured in the header of iMechanica: 

Hi......

       I have a accelaration vs time data for an earthquake. But I need velocity vs time data for an earthquake for dynamic analysis of a structure with this earthquake as input. The intrgration of accelaration is velocity. How I can integrate this numerical data? I have an idean about Newmarks beta method but how to use it? I have no idea. Is there any further simple method to do this? Is there any reference book or journal or link available for this?

Thanks in advance......

Sreenu 

volinsky's picture

US Student summer job IRES: International US-European Joint Study of X-Ray Optics Thermomechanical Stability and Control

Summer Job for Students in Europe: NSF-sponsored International Research Experience for Students (IRES)
International US-European Joint Study of X-Ray Optics Thermomechanical Stability and Control

 

[LS-DYNA] Attenuating vibrations of shell element after an explosion

Free Tags: 

Hello!

The model I'm working on in LS-DYNA is a simple pyramid-shaped shell constrained along the bottom edges with all DOF taken. The material used is MAT_PIECEWISE_LINEAR_PLASTICITY. Above the model there's a LOAD_BLAST (Air burst) placed, which deforms the model after the explosion.
The issue is that the model seems to vibrate ininitely after the explosion, what can be seen on the attached images (first one shows the graph of "Rigid Body Displacement", second one shows close-up of the line within the yellow rectangle).

Zhigang Suo's picture

Resistance Curve

These notes were initially written when I taught fracture mechanics in spring 2010, and were updated when I taught the course again in 2014.

You can access all notes for the course on fracture mechanics

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