Dear ATENA Friends,

We are happy to share the latest news from the ATENA world this summer!

ATENA 2026, our biggest release this year, is now officially available. It brings dynamic analysis directly into the native Engineering preprocessor, supports simulating 3D concrete printing from G-code files, and continues the development of a single unified platform combining ATENA Engineering and ATENA Science.

We have also launched the CC Store, our new online platform for annual ATENA licenses, and a new AI-powered support assistant to help You get answers faster.

Fig. 1: Jan and Martin sending greetings while sightseeing in Lisbon before the fib congress 2026.

On the events side, we exhibited our software products at the fib 2026 Congress in Lisbon as a Silver sponsor, and we look forward to hosting the SHNIPS Workshop 2026 at the Czech Technical University in Prague later this month.

We hope You enjoy this issue, and we look forward to meeting many of You at our upcoming events!

With warm regards from Prague,

Your ATENA Team

The major update ATENA 2026 has been released recently. Users with valid maintenance support can download the new version from the downloads section of our website. If you are unsure about the status of your subscription license or maintenance, please do not hesitate to contact us by email or phone.

New users are welcome to install ATENA and request a 30-day, fully functional trial license directly from the ATENA Center interface after installation.

Annual ATENA licenses, both single-seat and network, can now also be purchased directly through our new CC Store, using either of our two available payment methods.

Fig. 2: CC Store - new e-shop for online purchase of ATENA yearly subscription.

Fig. 3: ATENA Center 2026 is the main entry point to all ATENA applications and tools.

ATENA 2026 is one of our biggest releases in years, headlined by a unified preprocessor for ATENA Engineering. Here is a closer look at what is new.

Improvements in the unified 2D/3D Engineering preprocessor.

ATENA 2026 introduces further improvements in the preprocessor that combine the robustness of ATENA Science with the simplicity of ATENA 3D Engineering, unifying 2D and 3D modelling into a single, user-friendly environment. It brings stronger compatibility with ATENA Science, support for curved NURBS lines and surfaces, layers, user-defined material libraries, and a significantly improved user interface, all built on fully 64-bit technology for larger and more complex models.

ATENA 2026 can be downloaded here.

Dynamic analysis, natively in the Engineering preprocessor.

Statics, transport, and now also dynamic analyses can be prepared directly within the unified Engineering environment. There is no need to switch tools or interrupt your workflow. This makes ATENA 2026 particularly well-suited to seismic assessment, impact analysis, and vibration studies, all built on ATENA's specialized concrete material models. Creep and transport analysis remain available through ATENA Science with the GiD preprocessor, with further integration into the unified environment planned for upcoming releases.

Users with valid maintenance can download ATENA 2026 here.

Fig. 4: CAMUS III benchmark analysis in the dynamic module newly supported by ATENA Preprocessor 2026.

Fig. 5: In this 3D printed concrete wall example, the specimen printing was simulated first, and then after 20 days resting the compression load test was successfully replicated by numerical simulation.

3D concrete printing, driven directly by G-code.

As the construction industry rapidly adopts 3D concrete printing, ATENA 2026 introduces native support for modelling and simulating the process. The model and simulation are controlled directly from G-code files, the same format used by most concrete 3D printers to program the print head. There is no conversion step: you load the G-code, simulate, and get results, a genuinely unique capability in the world of concrete simulation.

Python scripting and broader data exchange.

The new preprocessor adds scripting support using the Python programming language, opening the door to custom automation and workflows. It supports import of IGES CAD data and  *.gid models. IFC support was also expanded, alongside a BIM-based internal data format.

AI-Powered Support Assistant

Earlier this year we launched a new AI-powered support assistant, available directly on our website, and the response from ATENA users has been fantastic.

The assistant is designed to answer technical questions on the spot, whether it is choosing the right material model for a particular concrete type, setting up a crack propagation simulation, working through reinforcement and bond-slip modelling, or interpreting results. No login, no waiting for office hours, just a quick answer when you need it.

What has struck us most is how users describe it. Many tell us it has become a genuine part of their daily workflow, a quick way to get unstuck without breaking their concentration on a project. For newer users especially, it is proving to be a valuable companion while learning ATENA's workflows and best practices.

Try it yourself, no login required: 
ATENA Siesta AI-Assistant 

Fig. 6: Our website with the AI-Assistant blue icon in the bottom right corner.

Fig. 7: Examples of parametric FE analysis using ATENA for various reinforcement detailing.

Load transfer between upper and lower concrete columns with variable sections under cyclic lateral loading

Ja-Hyung Koo, Jin-Young Park, Sung-Hyun Kim, Hong-Gun Park, Journal of Building Engineering,

Volume 119, 2026, 115323, ISSN 2352-7102,

DOI:10.1016/j.jobe.2026.115323. 

This nice paper presents an investigation of seismic tests on four column specimens with square-to-rectangular section transitions showed that capacity design in the lower column, with an overstrength factor, produced ductile behavior; without it, joint crushing or flexural compression failure occurred, cutting peak strength (Vtest/Vf = 0.73-0.95). Nonlinear finite element analysis in ATENA was central to explaining these failures, pinpointing inadequate reinforcement detailing and capacity design as the root causes and informing the design recommendations.

Master of Science Thesis from KTH, Sweden - Vinh Ho and Cindy Tong

A recent master's thesis by Vinh Ho and Cindy Tong used ATENA to investigate shear failure in reinforced concrete four-pile caps without shear reinforcement, building on Technical University of Denmark tests that revealed a clear size effect in shear resistance. Nonlinear finite element analysis reproduced the experimental load-displacement response and failure mode, captured the size effect, and supported a parametric study on concrete strength and slenderness, benchmarked against strut-and-tie calculations. It shows how ATENA can complement experimental testing with a closer look at crack localization and failure mechanisms.

Fig. 8: Mesh sensitivity study in ATENA simulation of pile cap experiment.

Fig. 9: Presentation of selected ATENA results from TU Graz at fib Lisbon.

Fracture-Mechanical Finite Element Simulation of Concrete Structures Using Smeared Crack Models

Authors: Dipl.-Ing. Yolcu Sever, Dipl.-Ing. Efim Griniov, Prof. Dr. techn. Dirk Schlicke

This article from TU Graz examines fracture-mechanical FE simulation of concrete members using smeared crack models, comparing the "Rotated" and "Fixed" approaches across bending, shear, and punching failure tests against experimental data. The fixed crack approach closely reproduced load-bearing behavior, ultimate loads, and crack patterns, while the rotated approach showed larger deviations depending on the failure mechanism. The study concludes that the Smeared Crack Model, applied with the recommended approach, effectively represents concrete's complex load-bearing behavior across research and practical design applications.

The paper is accessible via the following link on the Wiley Online Library.

Fig. 10: ATENA in person seminar 2024.

July 22, 2026 - SHNIPS project workshop, Czech Technical University, Prague, Czech Republic. In person event with free registration here.

July 19-24, 2026 - WCCM-ECCOMAS 2026, Munich, Germany, Jiri Kovar will present paper titled: FE modelling of concrete biological shield exposed to neutron radiation

September 9-11, 2026 - fib Ph.D. Symposium, BOKU University, Wiena, Austria, Martin Berka will join the conference exhibition and Jan Cervenka will deliver a special NLFM training seminar.

September 28-30, 2026 - ACI-fib-RILEM FRC Workshop, Budapest, Hungary, Martin Berka will talk to you at our ATENA stand and Jiri Kovar will present a paper on: Blind prediction of steel-fiber-reinforced slab punching resistance based on lessons learned from previous contests

October 5-7, 2026 - 15th Central European Congress on Concrete Engineering, Vodice, Croatia. Jan Cervenka will be one of the invited speakers.

October 11-14, 2026 - ACI Fall Concrete Convention, Atlanta, USA, as every year we look forward to joining the convention exhibition and to attending the committee meetings.

Fig. 11: It was great to meet our SHNIPS project team from South Korea at fib Lisbon.

Fig. 12: Great energy at fib Congress in Lisbon, always a highlight of the show for us.

CERVENKA J., CERVENKA V., RYMES J., KOVAR J., Blind predictions and uncertainty in the simulation of reinforced concrete structures, 21st International Probabilistic Workshop, Rostock, Germany, 10–12 Sept 2025, Study on uncertainty quantification in nonlinear simulation of RC structures. DOI: 10.1002/cepa.3354

CERVENKA J., KURMANN D., LACERDA M., AHMAD M., HULKOVA G., LEHKY D., NOVAK D., High-fidelity finite element modeling for seismic assessment of safety-critical structures in nuclear power plants, 7th fib Congress Lisbon, June 15–19, 2026

CERVENKA, V., CERVENKA, J., RIMKUS, A., GRIBNIAK, V., Model uncertainty of numerical crack width in reinforced concrete, Computational Modelling of Concrete and Concrete Structures 373–381 (CRC Press, London, 2026). doi:10.1201/9781003660026-44.

KOVAR, J, CERVENKA, J, CERVENKA, V, LEHKY, D, NOVAK, D, Refining Crack Width Predictions in RC Beams Using FEM and Neural Network-Based Surrogate Models for Crack Band Size Estimation, Computational Modelling of Concrete and Concrete Structures, EURO-C 2026, March 9-12, 2026, Seefeld, Austria, ISBN: 978-1-041-11408-6, DOI: 10.1201/9781003660026-76, Taylor&Francis Group, pp. 649-656

KOVAR, J., CERVENKA, J., KHMUROVSKA, Y., STEMBERK, P., FE modelling of concrete biological shield exposed to neutron radiation, Computational Modelling of Concrete and Concrete Structures 195–199 (CRC Press, London, 2026). DOI:10.1201/9781003660026-22.

REHOUNEK L., ZENISEK M., Numerical simulation and model validation of multispiral reinforced concrete columns under cyclic loading, Buildings, Vol. 15(21), 2025, Validation of multispiral RC column models subjected to cyclic loading. DOI: 10.3390/buildings15213855

BARROS J.A.O., SANZ B., MARCILIO FILHO M., KABELE P., YU R.C., MESCHKE G., PLANAS J., ET AL., Blind competition on the numerical simulation of slabs reinforced with conventional flexural reinforcement and fibers subjected to punching loading configuration, Structural Concrete, Vol. 26(1), 2025, International benchmark on punching resistance modelling of fiber‑reinforced slabs, DOI: 10.1002/suco.202400061

KOVAR J., CERVENKA J., KHMUROVSKA Y., STEMBERK P., FE modelling of concrete biological shield exposed to neutron radiation, 17th World Congress on Computational Mechanics (WCCM) 10th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) 19 - 24 July 2026, Munich, Germany

KOO J. H., PARK J. Y., KIM S. H., PARK H. G., Load transfer between upper and lower RC columns with variable sections under cyclic lateral loading. Journal of Building Engineering, Article No. 115323, Vol. 119, February 1, 2026, DOI 10.1016/j.jobe.2026.115323

SEVER Y., GRINIOV E., SCHLICKE D., Fracture-Mechanical Finite Element Simulation of Concrete Structures Using Smeared Crack Models, Beton‐und Stahlbetonbau 120.12 (2025): 1005-1017, DOI: 10.1002/best.70044