Hi Bekir,

Abaqus is another software you may want to consider. We use this software for non-linear, strain softening discontinuum simulation of rock masses with structures at various length scales. See some examples online at http://beckengineering.info/?page_id=62. Feel free to contact me if you have any further queries.

Regards

Alex

Dear Bekir,

You can use PLAXIS software to simulate the response of rock mas with discontinuities. In PLAXIS jointed rock mass model is available and it is capable of simulating your problem using Hock-Brown failure criterion. all the best in your research..

Thank you for your answers Alex Campbell and Karthigeyan . S , but as far as I know Abaqus and Plaxis use Finite Element Method (FEM) which is actually appropriate to apply only to Continuous media. If I am wrong, please don’t hesitate to tell.

Correct, Abaqus is FEM. We regularly build models is >100's of discontinuities for rock mechanics problems such as open pits and large underground mines.

Dear Alex, the problem is how do you implement the discontinuities in a rock mass to a FEM software which is based on continuum mechanics.

Dear Bekir,

ABAQUS is not based only on continuum mechanics.

You are right to say that the core of ABAQUS is based on the Finite Element Method but ABAQUS has (as many other comercially available software packages) many additional features like

(i) XFEM to model growth and initiation and fractures,

(ii) a variety odf different contact algorithm to model prescribed cracks,

(iii) DEM algorithms to model particle systems and even

(iv) SPH and the possibility to convert continuum tet elements into particles.

It really depends on the specific problem you want to model. If you look at the behaviour of granular materials pure DEM codes are best (Yade, Liggghts etc).

Simple static problems of hard rocks and soild can be solved with pure continuum codes.

In some, more complex cases you want to look at both aspects: the continuum behaviour of the intact bulk rock AND the behaviour of existing and newly created discontinuities.

Regards,

Fred

Thank you for your responses Frederik Reusch Alex Campbell Karthigeyan . S . I would like to model a relatively big area composed of a rock mass and the overall behavior is controlled by discontinuities. From this aspect, I would like to simulate the effect of discontinuities.

UDEC and 3DEC have been developed particularly for this case. Can ABAQUS or other softwares (Plaxis, ANSYSS, EDEM, YADE, LIGGGHTS etc.) reflect such an effect ? Also, implementing a strength criterion such as Barton-Bandis or Hoek-Brown is crucial for me.

Thanks

Hi Bekir,

There are several software packages you could use for this scenario. Another package you might consider is ELFIN. Each package has pro's and con's. You also need to consider how useable each package is to use based on your experience. We use ABAQUS because we believe it is it best package available at present for modelling complex rock mechanics problems. Please note we have no affiliation with any software companies.

As a recommendation, I would focus less on the software package and focus on collecting sufficient input data and to build the most representative structural regime and material properties as possible, as well as sufficient measurements for model calibration and validation. The most complex software package is not a substitute for incorrect input parameters or grossly simplified geometry / structural networks. The same rule applies for all models - rubbish in, rubbish out.

Dear Alex,

Thank you for your valuable comments. Currently I have no experience with Discrete Element Method but I think I have more than enough time (9-12 months) to learn the theory and the modeling techniques. In the mean time I will collect datas as much as possible. By the way, Do you have any recommendations on creating a representative 3D geometry of a complex structures such as open pits?

Thank you.

Regards

Bekir SF

The best way to develop representative 3D structural networks is mapping which includes orientation, persistence, termination, infill, roughness, etc etc. There is plenty of literature on the topic. Large and intermediate scale structures should be built explicitly in the model. You could also consider using a DFN generated from a steronet of mapped structures in each geotechnical domain. The level of detail really depends on the length scale of the problem you are trying to simulate.

Best of luck with the project

Alex

Thank you for your contributions Alex! I will keep in mind your suggestions.

Dear Bekir,

the ITASCA code to the distinct elements, UDEC or 3DEC, is undoubtedly what you need. It is very versatile, allows you to add custom routines and can do analysis in static and dynamic conditions.

I wish you good work

Dear Giovanni,

Thank you for your response. How much programming skills do you need to perform a decent analysis on UDEC & 3DEC? If any needed of course.

Regars

Bekir SF

If you work in the linear elasto-plastic field, using the Mohr-Coulomb or Hoek-Brown resistance criterion, you can do an @@analysis without programming. However, good experience is needed for the characterization of the geomechanical model.

UDEC, 3DEC, PFC

For 2D problems and to start UDEC is better; for 3D problems, of course, 3DEC.

Dear Bekir,

I think it's depend on your scope. UDEC and 3DEC are commercial software which use a lot in geotechnical modeling. RFPA is also another software for modeling. But, your issue ca be solved by considering equaled continuum method instead of a fractured/discontinuities media. Based on my experiences in the geomechanics issues simulation, firstly I prefer solve my problem as a continuum model.

Think about it!

Dear Bekir,

UDEC and 3DEC softwares are indeed well suited to analyze (in 2D and 3D respectively) a rock mass with discontinuities.

The Phase2 software (Rocscience) also makes it possible to carry out analyzes (in 2D) by integrating in particular networks of discontinuities (according to a statistical distribution of parameters of orientation, spacing, persistence).

I suppose the RS3 software allows for similar analysis, but in 3D.

Best regards,

Thank you all for your interests. I will try to simulate the problem by using continuum based programs where discontinuities can be integrated. Unfortunately UDEC and 3DEC are incredible high priced options even for academics. Actually I think I will try Abaqus and Phase2 first.

Dear Rouhollah, which softwares are you using to analyze that particular situation?

Regards to all

Bekir SF

I use a vast range of software such as UDEC, FLAC, Plaxis, Midas, and etc. for simulating the geotechnical issues. It's depend on my scope. Maybe, you can use ubiquitous model in FLAC software or jointed model in Phase2, RS, and Plaxis for considering the effect of discontinities.

Good Luck!

Dear Rouhollah,

Thank you for your contributions. Which softwares do you prefer to use for rock masses where high or low amount of discontinuities present?

Regards

Bekir SF

Only UDEC. PFC is also good but it is very difficult to work with as you do need to write subroutines in Fish language programming. Plaxis and Flac can address this. But be aware that such softwares are generic, while UDEC is specifically design for rock mass with discontinuities.

Thank you Ali,

Honestly I wish to use UDEC and 3DEC but I may not be able to because they are incredibly expensive. I will try to solve my problem with Phase2 and Phase3 as well as with Abaqus.

Regards

Bekir SF

UDAC, Plaxis

RocScience

Hi, accordind to your message, i can suggest you to use Rocscience Phase.

In the menu, at the boundary condition you can add the joint properties and then add the joint network for your joint set to the whole model (or only for a zone).

Dear Atul and Denis thank you for your responses.

Dear Luca, Can you add as many joints as needed to a model? Assume a rock mass consisting of 3 Joint sets which formed by 200 different joint measurements. I want to integrate all of the joints into the model. Is it possible?

Thank you

Regards,

Bekir SF

theoretically yes, then it depends on the geometric characteristics of the mesh that is obtained (vertices too close cause always problems). I worked on two groups of joints, because it is usually the most representative condition for 2D analysis. It counts that if you have too many joint families, perhaps the model becomes a "continuous equivalent", and no longer a discontinuous model (but this depends on the relative scale effect between your excavation and the geometry of the joints : "scale effect"). Bye

Luca

Thank you Luca. Do you think that it is possible to implement a joint network also in RS3? I couldnt find it on the rocscience’s website.

Thanks

Into the online help I've found

https://www.rocscience.com/help/rs3/pdf_files/theory/Constitutive_models_Manual/9-Jointed_Rock_Model.pdf

and

https://www.rocscience.com/help/rs3/#t=Geology%2FMaterials%2FJointed_Material.htm

Thank you very much Luca for finding such usefull examples.

Regards,

Bekir SF

I recommend the ITASCA software such as (UDEC, PFC, 3DEC). They are designed specifically to anaylze the behavior of discontinuous media such as rock masses Bekir Salih Firincioglu

If the process of destruction is not important, then Rocscience, for example, see "The Practical Modeling of Discontinuous Rock Masses with Finite Element Analysis" (https://www.rocscience.com/documents/pdfs/uploads/7704.pdf)

if it's important, then IRAZU (http://www.geomechanica.com/software) or you can see the Prorock ( http://teretau.com/en/prorock).

UDEC software can help

Dear Bekir Salih Firincioglu

I think the answer depends on your project's domain and of course, it's purpose.

I recommend you four pieces of ITASCA software: UDEC, PFC 2D, PFC 3D, and 3DEC. But you should pick the best one for your project between them.

Good luck with your research.

Mohammad

Rocscience

I recommend you UDEC.

Irazu

https://www.geomechanica.com/software

Rockfield

https://www.rockfieldglobal.com/software/elfen-forward-modelling/

I recommend you ABAQUS.

Dear Bekir,

For analysis of discontinuous environment using discontinuum approaches is required. You can try LEM, DEM, DFN, or DDA. See the following paper:

Article Numerical modeling of discontinuous rock slopes utilizing th...

Article Stochastic geometry model of rock mass fracture network in tunnels

Best regards,

I recommend you RFPA

Now choice is yours.

Dear Bekir Salih Firincioglu

I would recommend the Prorock, IRAZU, DEM, DDA or any ITESCA software like UDEC.

Best regards