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The auxiliary fields could be applied to the method for computation of SIFs for a dynamically propagating crack

Hi all,

Recently, I have read the paper "Dynamic crack propagation under mixed-mode loading- Comparison between experiments and X-FEM simulations" published in IJSS, 44 (2007), 6517-6534. I have met some questions on the choice of auxiliary fields for calculating the SIFs.  Could someone give me some details including the auxiliary velocity fields, the auxiliary displacement fields and the auxiliary stress fields. Thanks.



Slip system in monoclinic


Anyone knows how to find the potential slip systems in a monoclinic structure?

I have XRD data.


LEFM - Mode 1 Stress intensity factors (J-Integral) for inner cracks in pressurized thick-walled cylinders


During my thesis I am calculating mode 1 stress intensity factors (J-integral) for inner crack in pressurized thick-walled cylinders with ANSYS v13.

The loads are inner pressure on the cylinder bore and gas pressure directly on the crack plane.

I wanted to know why the J-Integral converge along part of the crack front (from the deepest point Phi=90 until Phi=60 degrees, assuming semi-circular crack) when loading the crack plane directly while with the inner pressure the J-integral converge along the whole crack path.

 Best regards


HussamNasreddin's picture

ABAQUS mesh systems

Hello all,

After performing an analysis step, could I remove an element from the mesh grid(thus, creating a geometrical change in the model) and then run another analsyis step? Is there anyway for ABAQUS to do this without me physically removing the element?


Hussam Nasreddin

crack propagation using XFEM

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hi everyone my name is sarah

i am new to abaqus.i wonder if anyone can help me. i made a crack propagation model in 2D.unfortunately the crack wasn`t propagated. Only there was a separation between the two surfaces where the crack line is in between. How can i make the crack tip propagates through the line drawn?


pictures and data of crack propagation experiment or example


I am looking for some data/pictures of crack propagation tests. More precisely, what I am looking for are test results of some 2D structure (or structures that can be modeled in 2D) where the experimenter has listed the geometry, material, loads and boundary conditions, and displayed photos of the crack that was observed propagating on loading the structure. Sort of like "heres a plate of dimensions a x b, made of material x, with an initial crack here, I now apply a load of magnitude M, and heres a picture of the crack that has propagated."

Cohesive crack - how to verify model? Cant figure out how to output stress intensity factor...


I am simulating crack propagation with cohesive elements. In order to verify that my model is working correctly I wanted to compare it to some real world data or benchmark examples. One such example is in the Abaqus Benchmarks manual - a flat plate with a crack in the center.

charpy test

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How to calculate the impact force at the time of impact for charpy impact test method

using XFEM in studying crack propagation

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deer all

i am having a difficulty in modeling a crack growth using the XFEM. what is the difference between specifying the crack path and when u don`t specify it? 

when i specify the crack path the surface separation begins even if i applied small loads value. But when i don`t specify the crack path it never separates.

Does anyone has an answer for me? thanks.

About J integral for curved crack

The well-known J integral is only valid for straight crack, am I right?

If no, can anyone please point me a reference for the J integral in case of curved crack?


SIF,COD and Critical Flaw size for a pressured pipe with axial and circumferential crack in ABAQUS

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Hello All,

I'm new user in ABAQUS and I want to simulate and verify a critical crack-size in a pressurized pipe with axial and circumferential crack. Also, an important aspect, the crack is through-wall thickness. So, I'm faced with some doubts about its implementation in ABAQUS as following:

1 - Can I model the through-wall crack with shell ements based on line-spring (element LS3S)?

How to estimate crack growth propagation using the maximum tangential stress criterion method?

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Hi All

 Currently I am running FE modelling using linear elastic fracture mechanics approach to estimate crack growth propagation in a web plate of box girder in an existing bridge deck. The FE model includes 3D solid element. The crack growth direction is expected to follow in a plan perpendicular to the maximum principal stress.

HussamNasreddin's picture

Elastic failure criterion

Dear all,

I would like to define an elastic material with a
failure value of maximum tensile strain only. Any element reaches a max.
tensile strain value will crack and suffer complete loss of load
carrying capacity(possibly delete that element). Thus its a change in
geometry that is only considered when redistributing stresses.

 Could this be done in ABAQUS or any other Finite Element Software?...I have been working with ABAQUS for some time now but I could not reach any where


Thanks for the help


Crack propagation in composites in presence of shear and pressure loads


Assume that we have a composite structure consists of isotropic layers with a delamination (separation) between the layers. There is a compressive load
applying normal to layers surfaces and hence normal to the delamination (crack) which closes the delamination, and a shear load tangential to the crack surface.

the order of shear force is much smaller than the compressive load. can the delamination propagate du to this shear force?

crack propagation in thin films

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I work in a thin-film photovoltaics institute.  We deposit 1 µm silicon on glass substrate.  This silicon has tensile stress.

Then, by etching through a tiny hole in the silicon with HF, we underetch the thin layer.  This way, a circular area of the silicon is unattached to the glass.  The circle grows with time. We observe spirals of cracks at these positions.  Sometimes, there's only one spiral, sometimes we see two nested spirals.

Pressure distribution in hydraulic fracture

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How to calculate the pressure distribution in hydraulic fracture? dp/dx=-12*u*Q/w^3 for Newtonian fluid,  If I do not assume the pressure in the tip equal to the normal stress.    

 Could I calculate the pressure of each element from the wellbore ? 

Dynamic Auxiliary Fields for Interaction Integral

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Dear friends,

Crack modelling in Abaqus with prescribed displacement problem


 I am modelling stationary Mode-I & Mode-II crack in a simple 2D plate on abaqus. My problem is a prescribed displacement problem i.e. I have to apply displacement boundary condition on the edges of a plate instead of tractions. I am a begginer on abaqus and need help in this regard. Moreover, I'll appreciate if anyone could give me some instructions or tutorials on analysing stationary cracks with both FEM and X-FEM.




need help..

can anybody tell which book to follow for basics of fracture theories...or any material regarding this....or any opinion will work...

Simulating crack growth in Ansys implementing Cohesive Zone Model (CZM)

Hello, everyone!

Could you, please, help me with the following issue?

I’m trying to simulate a crack growth in an anisotropic media using cohesive zone model (CZM), and the results I get do not agree with my expectations, based on a common sense and simple estimations.

As I don’t yet feel myself on a safe ground with APDL, I make use of Ansys Mechanical, implementing command objects where needed.

Modeling of a reinforced concrete beam under a rolling load.

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Hi, we're trying to model with ABAQUS a reinforced concrete beam under a rolling load. We want to investigate the compressive low cycle fatigue of reinforced concrete elements under a variable bending moment. We are using a Static Step (total step time: 18000 sec) and a concentrated force applied on the middle cross section with the following load history*:

smilehan001's picture

abaqus system error code 142

I used abaqus6.9 and intel fortran with UEL

The inp and fortran file is from 

Y.F. Gao*, A.F. Bower, "A simple technique for avoiding convergence problems in finite element simulations of crack nucleation and growth on cohesive interfaces." Modelling and Simulation in Materials Science and Engineering 12, 453-463, 2004

I encountered the 142 error code and don't know to deal with it.

Can someone help me?

Mtech thesis doubts

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Frown Want it urgently


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