Published: 3 March 2023
The latest releases of PLAXIS marks our definitive transition to becoming part of Seequent, The Bentley Subsurface Company, with some minor cosmetic changes and a change to the version numbering. Benefit from workflow enhancements for rock and mining engineers, a new material model and SoilTest options for users working with unsaturated soils. PLAXIS 2D enters the world of subsurface digital twins and PLAXIS Monopile Designer users can improve their designs with additional design criteria.
Import of Leapfrog cross sections from Seequent Central
With PLAXIS becoming part of Seequent, our products can start offering much tighter integration and workflows for subsurface digital twins. The first step of this integration is through the new Import geometry from Central option in PLAXIS 2D. The workflow involves Leapfrog Works or Leapfrog Geo as a starting point, to create a 3D geological model from the incorporation and interpretation of digital site investigation data. Once the 3D Geological model is completed, the model can then be sliced with arbitrary cross sections or a sequence of cross sections intervals along an alignment, or path.
Geological Leapfrog model
The 3D geological model and the cross-section can then be published to Seequents cloud based visualization and collaboration solution Central. The full project now hosted on Central acts as a single source of truth. Collaborators can download the latest copy of the model from Central and independently modify, update, and republish the model as a newer instance of the project.
Cross section of Geological model, as stored in Central
The cross sections published in Central can be accessed through PLAXIS 2D with the Import geometry from Central option. The user will be prompted to select the relevant server, project and latest published data and can then choose one of the available cross sections. Once chosen, the application will download the cross-section data and open the import dialog window to show the polygons that will be imported. Once accepted by the user, the geometry will be inserted into the project. The user can then proceed to add structural elements and loads to the PLAXIS model as usual. The new Central icon on the main task bar will reflect the status of the geometry inside PLAXIS. If someone publishes a new instance of the Leapfrog project into Central, PLAXIS will be notified by Central. The user can then verify if there are any geometric changes to their cross section and can choose to reimport the data if so. This way the user can always be informed on whether the latest geological information is used in the project and make it much easier to recognize and import that data from a verified single source of truth. Check out the movie below showing the entire workflow for a drift in an underground mine complex:
- Leapfrog Works: https://www.seequent.com/products-solutions/leapfrog-works/
- Leapfrog Geo: https://www.seequent.com/products-solutions/leapfrog-geo/
- Seequent Central: https://www.seequent.com/products-solutions/seequent-central/
Barcelona Basic model
The Barcelona Basic model (BBM) is a Cam-Clay type effective stress model for the behaviour of unsaturated soils. The PLAXIS version of the BBM is defined in terms of Bishop effective stress and suction as stress variables, with an improved yield surface to capture better stress triaxiality both for saturated and unsaturated soils. The most important features of the model consist of the capabilities to model both elastic swelling and irreversible 'collapse' deformation upon wetting, as well as shear strength decrease when suction is reduced. Therefore, the model is most suitable for collapsible and/or moderately expansive soil, such as low plasticity (silt, clayey sand, etc.) and granular unsaturated soils. The Barcelona Basic Model was implemented with scientific support from the Polytechnic University of Catalunya (UPC), where the model was originally developed. This support is gratefully acknowledged. The model is available in the Advanced and Ultimate tiers with a valid Geotechnical SELECT Entitlement.
For more information, read the Barcelona Basic Model documentation.
Temperature and Suction in SoilTest
The SoilTest facility now has the option to account for an initial temperature and/ or suction for almost all the test types, except the Pressure meter test type. For the General test type, temperature and suction increments can be defined per test phase to replicate real life lab tests during which the temperature and/ or suction are varied. After calculating a SoilTest, some new standard graphs are automatically added, showing the evolution of temperature and suction versus strain. These new options, available in SoilTest under the Options menu, allow users to calibrate model parameters for the more advanced material models in PLAXIS that may be derived from suction or temperature-controlled lab tests, like the Barcelona Basic Model or the Frozen/Unfrozen Model. While temperature support in SoilTest is only available for PLAXIS 2D Advanced or Ultimate with a valid Geotechnical SELECT entitlement, suction in SoilTest is available for the 2D and 3D Advanced or Ultimate tiers with a valid Geotechnical SELECT Entitlement.
Cable bolt in Tunnel Designer
The tunnel designer has been updated to include the Cable bolt element when defining the reinforcements. After adding reinforcements to a tunnel segment, the user can now select from a new drop-down menu called "Element type" in the property tree of the Reinforcements tab. A choice is given between "Cable bolt" or "Rock bolt". The former uses the new Cable bolt element, the latter still uses the approach of previous releases namely the embedded beam element. Some objects and bolt configuration options have been renamed, fully changing the command and scripting signature which affect the backward compatibility of existing scripts. With the Cable bolts now available in the Tunnel Designer it makes it much easier to define reinforcement patterns involving cable bolts, but also to change the properties of these patterns, like length, spacing or number of cable bolts, allowing the geometry changes to regenerate with the click of button.
Small enhancements and fixes
Decompose into segments command
PLAXIS 2D offers a new right mouse button context menu option called Decompose into segments that explodes polycurves into individual line segments. The individual line segments can then be assigned features, i.e. loads, interfaces, etc., also through the right mouse button. Since the original line is then used to assign the feature, the user can be ensured that no drawing mistakes were made. Together with the Create Polygon option introduced in the previous release, it makes working with imported geometry much more friendly and provides the user with more accurate model input.
SumPhase displacements for plates
From this release on, the way the SumPhase displacements for plates in PLAXIS 2D and 3D are presented have changed. This will now show the deformation results of the plate, or subpart, only since its activation, and so is more in line with user expectations and makes it easier to inspect and extract results for reporting or plotting purposes.
Due to this change, when opening a project calculated in a previous release, the SumPhase displacement results for plates (only) will show N/A. The project should be recalculated in this latest release in order to get the SumPhase displacement results for plates in the new format. Other results are unaffected by this change.
Simple example comparing SumPhasedisp-Y for sequentially activated plate segments
Solved known issues
- We fixed an issue in the PLAXIS Output Report Generator when including different structural material types. Read for more details.
PLAXIS Monopile Designer
Rotation failure condition
A new setting in Analysis mode enables specifying a maximum limit for monopile rotation at ground level, in addition to the current maximum displacement. The calculation will stop either when the first failure condition is reached or when the workload is fully applied without reaching failure.
N.B. By enforcing this additional condition, some calculations may reach failure sooner than they did in previous versions. To reproduce previous results, increase the value of the maximum rotation until it ceases to be the limiting factor.
Displacement controlled analysis
As an alternative to a workload, it is now also possible to specify a target displacement at mudline in the Analysis mode. Under displacement-controlled analysis, the calculation will proceed until the target displacement at ground level is reached, independently of the equivalent workload and failure conditions.
The displacement-controlled calculation also enables direct extraction of 3D numerical soil reaction curves for a layered profile, using the Design Verification model. This option requires PLAXIS 3D and a valid Geotechnical SELECT Entitlement.
PLAXIS Monopile Designer displacement control
So, update to our latest editions to benefit from these new features and software improvements using either the CONNECTION Client or by downloading the software yourself today!
Direct downloads and access to full release notes with all added features:
Deep Excavations, Retaining Walls, Shallow Foundations, Deep Foundations, Finite Element / Finite Difference, Rock Mass Characterization, Slope Stability Analysis, Underground Structures
PLAXIS, Seequent, Bentley, Leapfrog, Central
Looking for more information? Fill in the form and we will contact Bentley Systems for you. Alternatively, you can visit Bentley's website and speak with a Bentley Geotechnical Expert.