# opinion

## Plastic J significance in CTOD equation

I am working on the validation of CTOD.

In the evaluation of CTOD using the
J-integral approach as applied in ASTM E1290 and E1820, the plastic J
component is defined as (Npl*Apl)/(Bn*Bo)
Npl=dimensionless constant(plasticity)
Apl=area under load vs. displacement plot
Bn=ligamen length (W-a)
Bo=section thickness

On E1820 there are different functions provided for Npl if Apl is
evaluated differently (CMOD or load-line displacement).

## 2014.02.26

A new beginning of learning!

Be tranquille, and just do it.

——Time

## Solid Mechanics mini project

Guys , we've been given a mini project of solid mechanics to make any simple model which shows movement . We're getting short of time so please ....
I'm looking for some ideas of how and what to make .

## Solid Mechanics mini project

Guys , we've been given a mini project of solid mechanics to make any simple model which shows movement . We're getting short of time so please ....
I'm looking for some ideas of how and what to make .

## Hyperelastic and Viscoelastic material modelling

I have a doubt regarding the Hyperelastic and Viscoelastic material modelling in ANSYS using Mooney-Rivlin material constants.

ANSYS theory manual says that for large deformation and large strains, the material modelling (i.e. constitutive behaviour) is same for hyperelastic and viscoelastic. Is it so?

Generally,  Mooney-Rivlin material constants are used to model Hyperelastic behaviour (rubber-like materials).

## A question on plasticity

Recently, I have a question on the plasticity.As the plastic materials undergo the loading and unloading process. we can find the energy dissipation from the stress and strain relation curve. Then, my question is that the energy dissipation is generated during the loading process or unloading process?Thank you very much.

## FOR A SOCIALLY RESPONSIBLE UNIVERSITY

Given the complexity of present and
future global challenges, it is the university´s social responsibility
to contribute to society by understanding the full extent of its needs
and current and future problems, and to prepare it to deal with them
effectively and efficiently (CMES, 2009)1. In this sense, due to its
ability to take the lead in matters of knowledge creation, promotion and
dissemination, the university becomes the ultimate guidance governments
possess in their quest to find solutions to inequality and exclusion.

## What are my Open-Access options?

As many othes, I find myself in the position that my funding agency mandates some form of parallel publishing (or preferably OpenAccess) (as well as an Open Access policy from my university itself).

I've been reading through what author rights i retain with different publishers, and among the big ones very little rights are retained.
Elsevier allows preprints to be published only if it is voluntary. That is, they intentionally prohibit mandated parallel publishing to protect their profit.
Wiley had different rights with different journals, but my first hand choice simply didn't allow parallel publishing of any kind ever.

## Hooke's law

Choose a channel featured in the header of iMechanica:

Upto what limit is hooke's law really obeyed ? some books say that hooke's law is obeyed up to the proportional limit, while some other books say that hooke's law is upto the elastic limit ? what is the correct answer?

## thermodynamics equilibrium state vs. steady state???

I am not clear about two concepts: thermodynamics equilibrium state and steady state. It's easy to conceive of the following different two osmosis processes regarding thermodynamics equilibrium state and steady state, respecitvely.

## FEM analysis of composite plate in ANSYS

HI..

i am doing FEM analysis of composite plate[0/+45/-45/90]S in ANSYS. I just wanna now which material properties i have to give as input, lamina properties or laminate plate properties..??

waiting 4 an early response..

Regards

FURQAN

## thesis

hi everyone ,

im finding  the subject of my thesis(in master science) i will be glad if anyone offer me the subject with satisfactory future , my tendency is applyed mechanic in stress !

thank you

Hi

I am thinking of a SMART HEADPHONE for people who are listenning to the music all the time for their saftey an their convenience and the people who tries to communicate with them. How SMART? The danger for such people is that they can not hear the alarm of the danger, like the horn of a vehicle. And also, sometimes they are called but they do not hear and consequently they do not show any reaction. This is so bothering for other people.

The tech:

## help each other to solve our problems

Hi dear mechanicinas

we are here to help each other solve our problems.agree?

so why don' read others blogs?

I have written several blogs till now.but just afew people read them and just no one answer!

the  last one was"why I can't define composite layup in abaqus explicite"the error is parameter composite can not be used in abaqus explicit!

thanks

BEST REGARDS

## what the strain gauge rosette measures is in status of plane strain or plane stress?

I read some textbooks about mechanics of material. regarding strain measurement with strain gauge rosette, most of them regard it as  in the plain strain status.  But in my opinion, what the strain gauge rosette located is a fress surface. In this way, the thress stress components related to this plane, that is zz, zx, zy, should be zero, assuming that  the out normal of this plane is in the direction of Z axis.  then there are sigmaxx, sigma xy, sigmayy to be measured.  Is there anything wrong with my understanding?

## Are we going away from mechanics?

Hi all,
Let me clarify first. The topic is not about imechanica.org is going away from mechanics or not.

While we refer papers from say early 1900 to 1980's we can see a lot of fundamental developments, especially in mechanics.  In case of solid mechanics, from linear elastic solid mechanics to plasticity and non linear solid mechanics, Continuum mechanics , visco-elasticity, micro polar elasticity, finite deformation problems and a lot more .

## A little humor for your day...Cats using Abaqus

Hi everyone,

There is a video on YouTube now of a cat using Abaqus...more specifically, the Abaqus Knee Simulator (Abaqus 6.12 release). Hope it makes you laugh:

Have a great week!

Matt