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Distinct-Element Modeling of Jointed and Blocky Materials in 3D

Opt for 3DEC for cutting-edge 3D geotechnical analysis. Tailored for complex soil, rock, and structural simulations, including dynamic modeling and ground support. Elevate your solutions and check out the latest version, 3DEC 9.1!


What Kinds Of Problems Can 3DEC Solve?

Collapse mechanism for an ancient stone masonry tower subjected to seismic forces.

Simulation of a light rail train station showing exaggerated displacements in the roof.

Simulation of one of the Chenab railway bridge abutments showing the model jointing and displacement contours. Rock foliation was considered using the ubiquitous material model.

Modeling degradation of dual-purpose canisters storing nuclear waste using 3DEC.

Seismic event model to study fault reactivation of fractures near a generic deep nuclear repository with various region scales shown.

Thermal iso-contours along a nuclear waste emplacement drift.

Complex hydraulic fracturing showing pore pressures, fractures opening (apertures), fractures shearing, and simulated microseismicity.

Rock wedges around the cavern for a case shown in 3DEC.

Simulation results of hydraulic fracture and natural fracture pore pressure and rock failure from a shale stimulation.

Hydrodam powerhouse chamber excavated in jointed and faulted rock showing block displacements.

Simulation of a proposed geothermal site showing shear displacements along pre-existing fractures and synthetic (predicted) microseismicity.

Simulation of pore pressures within the rock joints surrounding a hydroelectric power dam.

Cumulative total displacement contours after a new cutback has been excavated in an open point mine with exposed faults shown as white lines.

Mine pillar model showing joint traces to evaluate a ground support design. Rock blocks in the roof undergoing a total displacement of at least 4 cm are colored yellow.

Model of an underground tunnel showing fragmentation (left); bolt displacements, axial forces, and block displacements (center); and maximum principal stress (right).

Bonded tetrahedral block model showing the extent of damage around an underground tunnel with Sigma1 stresses plotted on blocks.

Spherical rock specimen of bonded voronoi blocks showing interior block details

Virtual UCS lab test using a sample composed of bonded Voronoi blocks showing displacements (left, exaggerated 50x) and a stress strain plot (right).


Why Choose 3DEC?

Dive into geotechnical analysis with 3DEC, where powerful computational tools enable in-depth exploration of complex rock and soil behavior, including the ability to run two instances simultaneously. Discover why 3DEC is the ideal choice:
  • Small-strain mechanics (gridpoints remain fixed)

  • Large-strain mechanics (gridpoints move with displacement)

  • Effective stress (pore pressure)

  • Automatic factor of safety

  • Back-analyze failure and calibrate forward-prediction

  • Multiple, simultaneous failure mechanisms

  • Zone relaxation for gradual excavation and construction sequencing

  • Groundwater flow

  • Material flow

  • Synthetic Rock Mass (SRM)

  • Bonded Block Modeling (BBM) for fragmentation and fracturing

  • Service limit state (SLS) and ultimate limit states (ULS) based on displacements

  • User-Defined Contact Models (UDC)

  • Surface subsidence

  • Recovery and dilution

  • Coupled ground-structure interaction (beams, cables, piles, shells, geotextiles, liners)

  • Options available: Dynamics (earthquakes, blasting, vibration), Thermal, User-Defined Constitutive Models (UDM), IMASS Damage Model

  • 3DEC models use a combination of interactive tools and commands. 3DEC simplifies modeling with interactive features such as CAD file compatibility, built-in mesh generation, intuitive boundary skinning, and automatic stress initialization.

    For advanced meshing, use Griddle and Rhino 3D CAD to build and precisely mesh complex models as a 3DEC grid. Easily define groups in the model pane and assign constitutive models and material properties using the built-in database.

  • 3DEC utilizes multi-threading and optimized solutions for fast, responsive, and accurate simulations. Multi-threaded FISH and Python libraries provide extremely efficient model scripting when user customization is chosen. Users may also run two instances of 3DEC on the same computer simultaneously, cutting down on overall time to solution for multiple models.

  • 3DEC offers robust hybrid (DEM + continuum) simulation capabilities to model blocks of discontinuous material (jointed rock or masonry bricks). Blocks may be rigid or deformable (zoned) and may slide, rotate, move apart, or come together. Uniquely model groundwater flow within joints and through the ground between them.

    Couple mechanical, hydro, and thermal solutions. Dynamic analysis to simulate earthquakes and structural elements for ground support are available. Statistical joint set and DFN generation tools are built in. Advanced plotting tools, FISH scripting, and Python integration provide unparalleled model control and customization, while statistical tools and data import options expand modeling possibilities.

  • In conjunction with interactive tools, 3DEC uses commands to provide a compact representation of the model (as a data file) for repeatability, to ensure path dependency (excavation sequence and any other sequence of events, such as boundary conditions or material properties), and for flexibility.

    Intuitively structured commands, built-in contextual help, and command auto-completion help users learn and work with commands. Most user interface interactions are automatically translated into commands, so you can see how they are composed and reuse them. The built-in text editor makes creating and running models with commands efficient.

  • Seriously faster. Solve steady-state models up to 10x faster and run dynamic models 3x faster. Model saving, restoration, and plotting are now 3-5x faster.

  • Improved joint logic is based on contacts rather than blocks, and cutting no longer unjoins previous joints.

  • New look and feel with streamlined UI, improved information box, inline help at your fingertips, and better plotting.

  • Even more highspeed dynamics (10-200x faster) using the new Maxwell dynamic damping logic.

  • 3DEC 9 zoned models can be coupled to FLAC3D 9 models.

  • Nonlinear structural elements for advanced ground support analysis for beams and shells.

  • Three new constitutive models: Concrete, Columnar-Basalt, and Von-Mises.

  • Python has been updated to 3.10.5, allowing you to more easily add your own packages. FISH scripting includes multithreaded FISH splitting and operators for even faster modeling.

  • Improved BBM (Bonded Block Model)

  • Updated documentation and examples, log-normal distribution for DFN fracture generation, and Timoshenko beams to account for transverse shear deformation.

  • Improved Multi-Process Modeling

    Multi-process models contain two or more coupled or decoupled solutions (mechanical/static, fluid, dynamic, thermal, and creep). Significant improvements have been made to simplify multi-process models, making analyses easier to use and understand.


  • Better Scripting
    • Python can now access the built-in geometry logic (user-defined nodes, edges, faces, volumes, etc.).
    • The contourpy Python library (for calculating contours of 2D quadrilateral grids) is now built-in.

  • And More!
    • Grouping operations are now faster.
    • New Hoek-Brown curve fitting and plotting tool – then add these value as PROPERTY commands right into your model.
    • QT 6 user interface libraries have been updated:
    – User interface appearance is improved on high-resolution monitors.
    – No need to specify OpenGL Mode.
    • By place an * at the start of a command, all related warning messages will be suppressed.


3DEC Case Studies

Discover the benefits of 3DEC in practical geotechnical engineering scenarios with our curated selection of case studies. Explore how 3DEC's advanced modeling capabilities have made a measurable impact in real-world applications.

Mitigating excavation challenges at Stockholm's Odenplan railway station, delve into initial stress dynamics at shallow depths. Through meticulous sensitivity analysis using 3DEC, ITASCA deciphers the interplay of joint slip and rock mass dilatancy, illuminating unforeseen ground deformations. The indispensable role of numerical modeling in navigating uncertainties and shaping future stress management strategies in similar geological contexts is underscored. Download the complete case study for in-depth insights into this remarkable project.


Voyez ce que les utilisateurs ont à dire

"Les logiciels [ITASCA] comme FLAC3D, UDEC et 3DEC sont très puissants et conviviaux."
Jung Wang, PhD Candidate
"3DEC has proven to us that is a powerful numerical tool to analyze complex physics problems."
Luis F. Vesga, EDIFICA USA

Expand Your Capabilities With Software Options:

Expand your 3DEC software capabilities with our range of add-on options, designed to tackle diverse engineering challenges effectively. Explore our selection of options to customize your 3DEC experience.

  • 3DEC offers three-dimensional, fully dynamic analysis that extends simulation capabilities to a wide range of dynamic problems in earthquake engineering, seismology, hydraulic fracturing, gravity flow, blasting, and deep underground rockbursts.

    You can specify acceleration, velocity, or stress waves as an exterior or interior boundary condition and include wave absorbing and free-field boundary conditions. Simulate and record synthetic microseismicity for model calibration and validation. Dynamics supports ground-structure interaction, can be coupled to thermal analysis, and includes a Dynamics Wizard to pre-process ground motions. Couple dynamics to groundwater flow for analyses involving time-dependent pore pressure changes associated with liquefaction.


  • 3DEC’s thermal analysis allows the simulation of transient heat conduction for modeling geothermal, ground freezing, and nuclear waste applications. The thermal logic includes a highly accurate numerical formulation for short time scales that includes thermal-mechanical fluid coupling and a very fast analytical formulation for long time scales.


  • 3DEC’s user-defined model (UDM) greatly expands the software’s versatility by permitting users to develop their own constitutive models, using C++ scripting, to describe a custom material behavior for zones and joints (contacts). Templates and instructions are provided.

    Start by modifying one of the built-in models or create a new material behavior from scratch. UDMs can be automatically loaded into your 3DEC project and may be freely distributed (as a DLL file). ITASCA maintains a UDM Library on our website for users to share their UDM models.


  • 3DEC’s IMASS features a two-mode softening of yield surfaces, offering a refined approach to modeling. Notably, IMASS introduces a set of novel material properties and integrates cutting-edge techniques for apex correction, automatic testing, and property updates and management.



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