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It seems there are quite a few experimental studies [1,2] on the fracture properties of porous materials, like nanoporous low-k dielectrics, as a function of porosity. Can anyone point out some references on the theoretical part, like the available models, computational methods or analytical approaches that can capture microstructure information, including porosity, pore geometry etc. Interface delamination of porous materials is also of interest. Thanks.

Hello everybody,

The coupled differential equations need to solve as following:

Could you help me to discretize this systems and find the eigenvalue λ  numerically using finite difference method?

Thanks in advance,

lqkhai 

Dear fellows,

We will predict the fatigue life for the metal-ceramic multilyer devices subjected to cyclic load in service . Residual stresses are induced during  high- temperature process in the devices, which were known in the previous work. Considering the bimaterial interface as a weak plane, no  geometric discontinuity are taken into account, i.e., perfect interfaces are considered.

 How to construct the cohesive interface model (no initial crack)?

appreciate your advice in advance.

Hello

I would liketo make/model the contact crack in Franc3D, but in Franc documentation there is anything about contact. Can anyone help me? I'm sure it is possible, but I don't know how to do it.

Michael Borowicz

deal.II is a C++ program library targeted at adaptive
finite elements and error estimation. It uses state-of-the-art programming
techniques of the C++ programming language to offer you a modern interface to
the complex data structures and algorithms required for adaptivity and enables
you to use a variety of finite elements in one, two, and three space dimensions,
as well as time-dependent problems.

ALBERTA is an
Adaptive multiLevel finite element toolbox using
Bisectioning refinement and Error control by Residual
Techniques for scientific Applications. Its design is based on
appropriate data structures holding geometrical, finite element, and algebraic
information. Using such data structures, abstract adaptive methods for
stationary and time dependent problems, assembly tools for discrete systems, and
dimension dependent tasks like mesh modifications can be provided in a library.
This allows dimension-independent development and programming of a general class

Hello,

My aim is
to carry out calculation of 2D crack propagation with ABAQUS 6.6.

Section 11.4.3
“CRACK PROPAGATION ANALYSIS” is providing an overview of what the software can
do, and I must say I am disappointed, for two main reasons:

I teach Materials Science to undergraduate engineering students. We devote 2 or 3 lectures on Fracture where we mainly introduce Griffith's formula and the stress intensity formula. I face a difficulty in reconciling the two which I would lke to present here.

The Griffiths equation gives the fracture stress s for a given crack size c:

s=sqrt[2 E g/ (p c)] (1)

The stress concentration formula gives the max stress at the crack tip as

s=s0 [1+2 sqrt (c/r)] (2)

NB - I edited this post cause I wanna u know I fixed this problem, before you read, ...

_____________________________________________________

Dear all

I want run an abaqus simulation with a user subroutine written in C/C++.

I have downloaded one from abaqus online support system answer 737.

Hi everyone,