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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

Johnson Cook damage criterion for Alloy 718

Hi I'm looking for a Johnson Cook damage criterion for Alloy 718 (or Iconel 718) i.e. the constants (D1,D2,D3,D4,D5).

If anyone seen an article or book with these constants I would be thankful if you could help me out.

Thanks in advance

cohesive zone with curvature


Anyone have experienece of curved cohesive zone model?

I just find people just use straight line cohesive zone geometry model.

Any difference between these two geometries?


cohesive zone model simulation :abaqus standard mode or explicit mode?

Since the available literature related to cohesive zone model simulation is done in abaqus standard mode, I'm curious if it is suitable to simulate in abaqus explicit mode.

Could you give me a suggestion?Thanks.

Composite Damage model

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   Everybody I am trying to design a composite layup and to design a
bulleye hitted by a blunt bullet  and need to do element deletion on it
by using hashin damage model in abaqus but I am new to abaqus please
help me regarding designing of lamina ,failuremodel and element deletion

Starting out question

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This is my first post so bear with me.

I have a question and an answer but have little idea how they got the answer.  The question relates to a sample with load being applied at both ends.


mathematical equation for a crack in a ductile material

hi all,

im an engineering doing a project on crack behaviour in a ductile material(mild steel) when a load is applied on going to analyse it using ANSYS, for validating this i need a mathematical plz if you have mathematical equations and journals regarding it plz reply me ...thank you... 


Literature regarding the appearence of cracks in steel. Thermal, pressure fatigue

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I am wondering if anyone could recomend som literature for me to get my hands on.
If there is any literature regarding how the appereance of a crack in a piece of thin metal (~0,5mm - 1 mm) could be related to pressure fatigue or thermal fatigue.
Does the crack due to thermal fatigue have a specific appereance and so on. I need get my hands on practical pictures and so on, not equations.
Are there any signs in the vicinity of the crack that is indicating that this could be due to pressure fatigue.

Any help is much appreciated.


3D modelling of an ellliptical crack in ANSYS

I am a beginner in FEM and just started using ANSYS.  I need to study the stresses and SIF at the crack front of an elliptical crack inside a material subjected to a stress perpendicular to the crack plane.  Any details on how I should build my model?  

What is the easiest way to define a cracked area, and crack front and then mesh it

How can i merge together a cracked area and an unmeshed area? 

I found a lot of links and articles that states they did it, but none explained the procedure do do it. 



Pooyan's picture

Failure Criteria


I want to know in Ansys software, what are the failure criteria values for steel in picture below?


Failure Criteria 






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