to our spring newsletter 2019
friends of ATENA software,
hope this newsletter finds you well and busy with interesting and rewarding
of things have changed in our company since the release of our previous
newsletter last autumn.
is the most important, during the past year we hired 4 new engineers/programmers
and 3 new part time students, employees to cover the increase in software sales,
consulting and research projects. We stay very focused on their thorough
completion. On top of it, we invested a huge amount of efforts in our
ATENA software development to make it more friendly and robust
from the users' perspective.
our software starts to be more and more recognized in the world, we decided to
take part in many conferences and events worldwide. Please, see the section
below for the list of the professional events where you can meet us presenting
papers, having a stand or just chatting with you during a conference dinner -
what matters is getting closer to you and knowing your current
look forward to cooperating with you or seeing you somewhere around the globe.
The world seems to be surprisingly small sometimes :-).
best regards from Prague
1: The display of cuts and internal forces diagrams of cracked concrete
structures have been further improved in the new ATENA version
Release of ATENA Software Version
ATENA version 5.7
is released in June. It contains important improvements to the various features
introduced in the previous years. These improvements were triggered by the
feedback of our users and clients.
Better performance in solving and
post-processing large scale analysis
software is becoming the premier solution for checking the design or assessment
of large and safety critical structures. It is therefore often useful to develop
large scale complex models involving various element types: - 1D/3D beam
elements – 2D/3D shell elements – 2D/3D solid elements. ATENA supports standard
1D beam and 2D shell elements. In addition, it includes special 3D beam as well
as shell elements, with only displacement degrees of freedom. This simplifies
the development of complex large scale models, where it is useful to combine
beam and shell elements with solid elements. Beam and shell elements can be
effectively used in areas with dominantly bending behavior, while critical shear
dominated areas can be modeled by solid elements. Based on the feedback of ATENA
users as well as our own experience of using ATENA in large scale analysis of
tall buildings, we have improved the speed of analysis and
namely postprocessing almost 100 times compared to version 5.6.
Such large models are demonstrated in the figures in this newsletter, which
shows results from performance based design of a multistorey buildings supported
by nonlinear analysis.
modeling - new model for Alkali-silica-reaction in
Alkali-silica reaction (ASR) is a reaction in concrete
between alkali hydroxides and reactive siliceous aggregates. This process causes
the development of expansion strain in concrete, which may cause secondary
cracking and can significantly reduce the concrete strength.
2: The analysis of large scale problems is more effective allowing you to model
your structures with even more detail.
3: ATENA unique durability models also allow the modelling of chloride ingress
and carbonation and their impact on reinforcement corrosion
new material is part of our ongoing effort to provide engineers with an
efficient tool to evaluate the durability of reinforced concrete structures.
ATENA models now cover the most important aspects of durability of reinforced
concrete structures such as chloride and carbonation process, reinforcement
corrosion and ASR. The durability features are all available now in the new
version 5.7, and they have been developed during a research project DURACERV
funded by Czech Technological Agency under the project
in the run-time and post-processor program ATENA Studio
has by now become the most popular software in the ATENA simulation system. It
allows runtime visualization of the analysis process as well as full
post-processing capabilities even while the analysis is still running and the
iterative process is not yet completed.
4: The new feature of tensor or vector plots can be combined with standard ATENA
crack display to create beautiful figures providing great insight into the
stress flow affected by crack development.
5: The improvements in the post-processing of large scale models is demonstrated
on this display of cracking around the containment access hatch.
very useful insight into the iterative process helps to discover any modeling
errors and gives useful hints how to eliminate any divergence problems. This
program has been further improved in the version 5.7.
- faster post-processing of large scale models,
speed increase almost 100 times
- new display of local element coordinate
systems, especially useful for beam and shell elements
- new colored
display of tensorial quantities such as principal stresses and strains
new colored display of vector quantities of forces and displacements
improvements in the visualization and definition of moment, normal and shear
force diagrams and 1D evolution graphs of beam and reinforcement
- plus many other minor improvements and
new features and improvements:
The latest version of Microplane M7
model from Prof. Zdenek Bazant and Prof. Ferhun Caner has been implemented to
improve the behavior of M7 material model for the modeling of brittle materials
such as concrete, rock or masonry.
Improvements in the tensile fatigue model
that enables to consider the fatigue damage in concrete material in high cycle
6: Principal compressive concrete stresses in the pre-stressed nuclear
containment including the base sub-structure was also modeled in the new ATENA
in the cloud
in the cloud. Our new product, the ATENACloud just reached a public
BETA version, and we would like to invite You to try it.
allows you to use our software
ATENA and other tools on cloud based computers. These are created instantly,
with all needed software pre-installed.
can be uploaded/downloaded via this web application. To connect cloud computers
created via VTLS you will need some RDP
client software. Computers can be operated from any operating systems
including mobile platforms iOS and Android.
7: ATENA software can be easily evaluated using our online ATENA cloud
simulation of 3D printing of concrete
new module for ATENA has been developed to simulate and
optimize the printing process and speed. The video
shows an example analysis when too fast printing results in the wall
printing module shows a procedure of such an analysis on the basis of nonlinear
FEM, and it describes all extra features that are needed for such a simulation.
These are mainly modelling of the detailed construction process of the
structure, time variable load and suitable nonlinear constitutive equations for
times ranging from fresh to mature concrete conditions. The newly developed
computation modules are implemented into software ATENA (Cervenka et al 2018),
which is later also used to compute a few sample analyses. The structure is
first modelled at its final size and shape neglecting its construction process.
Then, based on the prescribed motion of the printing head, a time for the
activation of each element is calculated. The next step is the simulation of the
manufacturing process. It is carried out at time steps, whereby at each step at
a given time the FE model of the structure consists of active elements only and
the rest is ignored.
printing module is part of an international research project digiCON2, where the
presented model will be used to optimize the path and speed of the printing
process and for the verification of the structural stability of the printing
process as well as of the final structure during its service life.
8: Deformed structure with maximum lateral deformation and the cut with the
of an Armed Concrete Slab and Break Load
software is widely being used in practice in both sectors, commercial and
academic. Moreover, we have just received a fresh notification by José Joaquín
Ortega and Lucia Garijo from the University of Castilla-La Mancha informing us
that they were declared as the winners of the blind prediction competition and
obtained the prize using ATENA. For your illustration, we are enclosing two
pictures from our Spanish colleagues showing the behaviour of the concrete
9: Damage of the concrete slab
10: CAD-model imported to ATENA
non-linear finite element analysis of concrete buttress dams
Master thesis of Science in Civil Engineering at Luleå Tekniska
the thesis set out to achieve was to compare analytical calculations in some
failure modes to a non-linear finite element analysis and to attempt to quantify
the importance of these often disregarded for features. A section of the
existing Kalhovd dam in Norway was chosen as a large amount of
information about this buttress dam had been gathered. It had also undergone
assessment in 2016 (with analytical methods) where this section of the dam had
been deemed unstable.
2D was the chosen finite element software for the project as it offered
a module that allows for probabilistic analysis. This granted the possibility to
test structural integrity with varying material parameters simulate material
degradation and observe what influence the randomized parameters had on the
behavior of the structure.
The results gathered from the deterministic
analysis in ATENA showed that the structure was able to
withstand the required loads by the Norwegian standards just by adding a more
realistic representation of the section’s foundation. Further addition of
discrete reinforcement to simulate the present rock bolts improved further upon
the stability, well above the called for capacity.
11: Principal minimum strains [-] at final load step (left). Principal (minimum)
stresses [MPa] at last load step (right)
12: Load-displacement diagram of probabilistic simulations of model 5
the probabilistic analysis with SARA, with the intent of
investigating material parameters and their affect on the structure, the five
chosen variables had little impact on the structure with the loads positioned on
the structure as stated in the codes, even with very sub-par parameters. It was
only when, the position of the force simulating the ice load was lowered closer
to the foundation and not at the crest of the dam (as previously modelled), when
the material parameters weighed in on the stability.
The reasoning for this
is due to the failure mode observed for the structure. It displayed a very
dominant overturning failure when including the foundation geometry, whereas for
a flat foundation geometry, the structure showed more of a combined sliding and
from the study showed that when accounting for the asperities of the foundation,
the failure mode of the structure changed. This increased the capacity of the
structure massively. The finite element analysis also allowed more than one
failure mode to be present/evaluated, whereas impossible for the analytical
calculations. The probabilistic analysis showed that the material parameters
were of little importance to the overall stability as instability of the
structure or loss of function was achieved before any local failures could be
13: Cracking pattern of simulation 1 at the final load step
most interesting in this project was found the probabilistic analysis and how it
showed clear distinctions between e.g. crack openings of the structure depending
on which parameter values the model was given. This led to an understanding of
the material parameters impact on the structure, which won’t be revealed in a
Advanced User Seminar 2019
users of ATENA software,
would like to invite you to our ATENA Advanced User Seminar
2019. The seminar in English language will take place in
Prague, the Czech Republic on June 12-14, 2019.
2016 the content of the seminar was rearranged compared to the previous years.
We decided to concentrate on fewer topics, but provide deeper coverage and more
hands-on experience with particular problems. Based on the feedback from our
hotline support, we selected several topics, where we expect that ATENA users
could benefit most from more in-depth explanation or background
14: Come to see Prague in summer and join our ATENA user seminar in June.
15: ATENA seminar 2018.
- Overview of new ATENA version 5.7
- Modeling contact problems in ATENA
- Modeling strengthening of reinforced concrete structures
- Modeling of construction process in ATENA for bridges and tunnels
- Modeling of fiber-reinforced concrete structures
You Can Meet Us
SEI Structures Congress 2019
Modelling in mechanics 2019
fib Symposium: Innovations in materials, design and
Underground Construction Prague
Prague, Czech Republic
Central European Civil Engineering
NAFEMS World Congress
FramCos-X: Fracture Mechanics of Concrete and
Udon Thani, Thailand
The Seventh International Conference on Structural
Engineering, Mechanics and Computation
Cape Town, South Africa
Fibre Concrete 2019
Hradec Králové, Czech
J., AL-SAUDI A., PRYL, D.: Modelling of High-cycle Fatigue Crack Growth in
Concrete, 10th International Conference on Fracture Mechanics of Concrete and
Concrete Structures FraMCoS-X, G. Pijaudier-Cabot, P. Grassl and C. La Borderie
J., CERVENKA, V.: Model Uncertainties and Global Safety Formats for Reinforced
Concrete Design by Numerical Simulation, NAFEMS World Congress 2019, June 17-20,
Quebec City, Canada, (acknowledgement cyberBridge)
J., JENDELE, L., VAITOVA, M.: Simulation of digitally printed concrete
structures using 3D extrusion, NAFEMS World Congress 2019, June 17-20, Quebec
City, Canada (acknowledgement digiCON2)
G., PUKL, R., CERVENKA, J., SASEK, L.: Tools for back analysis of geotechnical
constructions, Undeground Structures, Praha, CR, 2019
L., CERVENKA, J., VAITOVA, M.: FEM modelling of digitally printed concrete
structures using 3D extrusion, The Seventh International Conference on
Structural Engineering, Mechanics and Computation (SEMC 2019), Sept. 2-4, Cape
Town, South Africa (acknowledgement digiCON2)
L., NOVAK, D., PUKL, R.: Probabilistic and semi-probabilistic design of large
concrete beams failing in shear (SEMC 2019), Sept. 2-4, Cape Town, South
D., LEHKY, D., PUKL, R.: Fiber-reinforced cementitious composite: Sensitivity
analysis and parameters identification, Advanced Material Congress, Miami, USA,
December 8-13, 2019
R., CERVENKA, V., NOVAK, L., NOVAK, D.: Shear failure of very large concrete
beam: Nonlinear, probabilistic and semi-probabilistic modelling, CSM8, Paros,
Greece, June 2018
R., LEHKY, D., LIPOWCSAN, M., NOVAK, D.: Numerical model and sensitivity
analysis for parameter determination of fibre-reinforced concrete, Fibre
Concrete Praha, CR, September 17-20,