Cervenka Consulting Forums

Interface 3D and construction process incompatibility

2026-04-20T11:32:28Z

Hello,
I’ve been having a hard time with interfaces in ATENA 2025 Engineering.
In the model I assigned two Interface 3Ds between solids, and the analysis runs. However when I try to inactivate one of these through the ‘ Construction process’ option in the ‘Task’ input window, I get the following error:
‘Writing construction process "interface_mono" ended with an error due to unknown GROUP ID.’
(The other interface presist throught every construction stage so I did not include that in the tables, and I do not get the error message regading that)
I have checked the INP file and it suggests that there is actually two group ids assigned:

ELEMENT TYPE ID 131 NAME "Interface 3D wedge" TYPE "CCIsoGap" LINEAR
ELEMENT TYPE ID 132 NAME "Interface 3D quad" TYPE "CCIsoGap" LINEAR

ELEMENT GROUP ID 120001 NAME "interface_mono 3D wedge" TYPE 121 MATERIAL 85 GEOMETRY 12000 ;
ELEMENT GROUP ID 120002 NAME "interface_mono 3D quad" TYPE 122 MATERIAL 85 GEOMETRY 12000 ;

In case of other elements it looks the following:

ELEMENT TYPE ID 71 NAME "BE #7 Tetra Plate" TYPE "CCIsoTetra" LINEAR ;
ELEMENT TYPE ID 72 NAME "BE #7 Pyram. Plate" TYPE "CCIsoBrick" LINEAR ;
ELEMENT TYPE ID 73 NAME "BE #7 Wedge Plate" TYPE "CCIsoWedge" LINEAR ;
ELEMENT TYPE ID 74 NAME "BE #7 Hexa Plate" TYPE "CCIsoBrick" LINEAR ;

ELEMENT GROUP ID 70001 NAME "Plate" TYPE 71 MATERIAL 75 GEOMETRY 7000 ;
ELEMENT GROUP ID 70002 NAME "Plate" TYPE 72 MATERIAL 75 GEOMETRY 7000 ;
ELEMENT GROUP ID 70003 NAME "Plate" TYPE 73 MATERIAL 75 GEOMETRY 7000 ;
ELEMENT GROUP ID 70004 NAME "Plate" TYPE 74 MATERIAL 75 GEOMETRY 7000 ;

It would be important to remove it in certain intervals because if I exclude it from the construction process table the analysis crashes(it basically floats between the assigned solids), but I cannot start the analysis by deactivating it due to the INP error.
I was wondering if there is a way to either cut down to one group ID or are there any alternative solutions to this type of error, maybe I skipped a crucial step when assigning the interface or creating the mesh, since it might be a mesh incompatibility problem.
I have also tried to run the ‘interface3D with shear’ tutorial (available under the ‘Tutorials’ in ATENA center) by inactivating the interface in interval one, but I get the same error message.
It is also worth mentioning that the analysis runs when I delete the interface from the model and it behaves as expected under loads and according to the set construction process.

Thank you in advance for your advice

Cracking at master-slave (fixed contact for surface) connections

2026-03-19T15:10:29Z

I'm modeling a relatively complex geometry concrete beam in ATENA Science-GiD. In order to use the hexahedral mesh, I modeled the beam using smaller (all 6-sided prisms) volumes and connected those using a combination of shared surfaces and master-slave (fixed contact for surfaces) connections. All volumes are assigned the same material properties and mesh size. The mesh is assigned Mesh>Structured>Volumes>Assign size to volume lines. Mesh size is 2 inches for all geometry.

The results show cracking at some of the master-slave connections, mostly at corners. Is this caused by the master-slave connection, mesh settings, or something else? How can I fix?

Thank you for your help!

Punching flat slabs with strengthening capital

2026-02-20T12:29:54Z

Hello! My name is Arseniy Kovalkov. I'm a student and I'm trying to model an experiment at ATENA. The task is to simulate the punching of a flat slab with a reinforced concrete strengthening capital. The capital is arranged using shotcrete after gaining strength of the main structure. The contact concrete surface is treated with sandblasting equipment. I simulate friction using Interface only using the coefficient of friction (I simulate dry friction) at the points of contact of the capital with the column and the slab. Can you tell me if this is the right thing to do? If not, what is the best way to simulate such an experiment?

Concrete beam faliure in compression

2026-02-12T22:01:57Z

Hello everyone,

I apologize if this topic has been asked before, but I did not find an answer.

I am modelling concrete beams produced with FRP tensile reinforcement, following a series of laboratory experiments, with the aim of replicating the results in ATENA. The experimental beams all failed in compression as designed. The problem I have been encountering is that the beams in ATENA fail in shear. This is true with concrete material models generated based on Modelcode as well as user defined properties based on accompanying measurements done in the laboratory. I have tried adjusting many variables, increasing the shear reinforcement beyond the actual values but the mode of failure remains inaccurate. Older experiments with different geometry, but similar mode of failure have been successfully replicated.

I thank you for any help in advance!

Interface between concrete cylinder and loading plate

2026-01-20T21:18:35Z

In my model, I have created a contact volume between the concrete cylinder and loading plate at top and bottom by selecting the interface surfaces.
After that I am confused how to assign interface properties to the contact volume?
When I select interface---assign --- volumes ---- I don’t know how to assign it to the contact volume?

I am also confused how to select the created contact volume ??

Only if we could select that, then we need to mesh it.

How to mesh this contact volume?

We couldn't see any volume there as contact voulme right ? then we can select only that both surfaces.

Problem in ECC modeling

2025-12-10T10:37:13Z

Hello everyone,

When I run my model with the "Cementitious2 SHCC HPFRCC" material model in GiD, it diverges from the very first step and an irregular shape appears in the model from the beginning. please guide me on how to resolve this issue.

how should I set the "Fiber Reinforcement" and "Tension-Compressive" parameters? what are the "Fiber Cross Section Factor" and "Fiber Shear Modulus" ?

modeling reinforced concrete shear wall

2025-12-08T09:25:21Z

Hello everyone,

For my Master’s thesis, I am modeling a simple reinforced concrete shear wall from an experimentally tested specimen presented in a paper, in order to obtain the shear wall’s load carrying capacity. I am first performing validation, but I’m facing some issues and I have a few questions:

1. My results under monotonic loading show some differences. How can I improve them?

2. The paper does not provide the load protocol, although the specimen was also tested under cyclic loading. I also want to run the model under cyclic loading, but in GiD I don’t know how to define the cyclic loading to match the paper’s results.

3. Another issue in validating a beam is that my model’s stiffness is too high and differs from the experimental results. How can I improve it so that my results match the experimental data?

Thank you in advance for your guidance.

Meanings and Determination Methods of Load Step, Interval Multiplier,

2025-11-10T13:30:53Z

Hi everyone,
I would like to know what number of load steps , Interval multiplier and step multiplier mean and how they are determined. Are they chosen arbitrarily, or do they vary depending on each problem? Is there a specific formula for determining them? Please explain this to me in detail.

I have encountered a serious problem in my project — I’ve been working on it for several weeks but haven’t been able to solve it. The issue is that I’m trying to verify a beam model based on a published paper and perform the analysis in ATENA. The paper also used ATENA software, but my results do not match those presented in the article.

I have already gone through all the troubleshooting steps, but the problem still persists. One of my main concerns is how to define the loading and the load steps correctly in my analysis.
I would really appreciate it if someone could guide me on this.

Article or Main model of the shear wall examined in Example Manual

2025-11-06T15:37:46Z

Hi everyone,

Do you know which article the shear wall discussed in ATENA_Engineering_Example_Manual section 2.10 titled "Shear Wall with opening (SWO) " is taken from, or where it is sourced from in general? I mean, what is the source? Because it is not mentioned there.

And do you know of any article or manual where the shear wall is modeled with ATENA? I would appreciate it if you could provide it to me.

Post-Processing not working in ATENA-GiD (Trial Version)

2025-11-06T10:24:18Z

My name is Nhat, and I am using the trial version of ATENA-GiD
(ATENA Version 7.0.0.24694 and GiD Version 17.0.1).

I followed the steps in ATENA Program Documentation – Part 4-6: ATENA Science – GiD Tutorial.
Everything works fine during the analysis (both in ATENA Studio and the ATENA Console),
but the Post-Processing in GiD does not work.

After the analysis finishes, I switch to Postprocess mode →
click the button “Import Results from ATENA Win”,
and then the following warning appears:

“Sorry, but couldn't find the mesh information file
...\AtenaCalculation\AtenaResult.flavia.res.msh (or ‘-.bon’ or ‘-.dat’).
If the results file was calculated inside the program, try first loading the GiD project,
and then use the ‘Postprocess’ option.”

I checked the AtenaCalculation folder and found that the file
“AtenaResult.flavia.res.msh” is indeed missing.

I also searched for documents or forum topics about this issue but could not find anything.

Could you please help me solve this problem?
Thank you very much!

Questions regarding section 2.2.4 of ATENA troubleshooting

2025-10-31T16:01:43Z

I want to model a beam with UHPFRC concrete using the user-defined material (2.2.4 I want to use the user-defined stress-strain law of concrete to replace that used in ATENA program. How can I do it?) in ATENA’s troubleshooting section, following the tutorial. I have a few questions:

1. According to ATENA’s troubleshooting instructions, do I only need to apply the tensile part from the Excel file(http://www.cervenka.cz/assets/downloads/Atena/HordijkUser.xls .)? Is there no need to make any changes in the compressive tab or Tensile strength reduction tab?

2. In Excel (http://www.cervenka.cz/assets/downloads/Atena/HordijkUser.xls .), do I need to enter the strain column myself according to the uniaxial tensile stress–strain curve?

3. In the diagram I will attach, the uniaxial tensile stress–strain curve has three phases — linear, strain hardening, and strain softening. How should I enter this into Excel(http://www.cervenka.cz/assets/downloads/Atena/HordijkUser.xls .), and how should I model it overall?

I would appreciate answers in the same order as my questions. Thank you very much.

Problem Preventing ATENA Trial Application

2025-10-24T13:35:39Z

I am experiencing a critical issue that prevents the successful application for the 30-day trial of ATENA Engineering 2024.
After filling out the "Get a 30-Day Free Trial" form within the software and clicking the "Apply for a 30-Day Trial" button, the application interface immediately turns into a blank white screen. The process halts completely at this point, with no success message, error notification, or any further interaction possible.
Could your technical team please investigate if a recent update on the server-side might be causing this interface failure?

RC beam in a thin-walled steel formwork

2025-10-24T08:35:05Z

I want to model the behaviour of a RC beam cast in thin-walled steel formwork. The idea is that the formwork is part of the load-bearing element, and I want to model their cooperation during loading. And here I have some doubt:

1. Is the only way to model thin-walled C profile (thickness 2 mm) and connect its web and flanges is to use solids and master/slave connection, or is there a way to do it with 2D elements?

2. I tried to create solids and then assign to them Shell 3D elements, but I got a message saying that there was a problem with LCSs. How to fix this? How to check and change solids to make it work?

3. I also received a message saying that they do not recommend using Shell 3D with a single layer that is only 2 mm thick. Should I be concerned about this message?

reinforcement Bond model

2025-10-22T13:29:00Z

When do we need to use the reinforcement Bond model? Is it always necessary?
In modeling a shear wall made of ECC concrete or a beam with the same material properties, should we use it as well?

Dynamic analysis with GiD

2025-10-08T15:22:30Z

Dear,
I am writing to kindly ask for your feedback on our model. We are running a dynamic analysis in two intervals using GiD to model a 2D plane stress RC frame:
Interval 1: Self-weight only
Interval 2: Transformation of the central column material into a soft material elastic (simulating one column removal)
Do you have any recommendations on how to set the parameters for this kind of analysis? Thank you.