3DEC is three-dimensional numerical modeling software for advanced engineering analysis of soil, rock, blocky structures, structural support, ground water, and structural support. 3DEC simulates the response of discontinuous media (such as jointed rock or masonry bricks) that are subject to either static or dynamic loading. The numerical formulation is based on the distinct element method (DEM) for discontinuum modeling. UDEC is the two-dimensional equivalent.

A discontinuous medium is modeled as an assemblage of polyhedral blocks that may be rigid or made deformable through zoning. The discontinuities are treated as boundary conditions between blocks and a variety of material models for zones and/or contact models for discontinuities (such as joints) may be assigned to represent different materials and behaviors. Large displacements along discontinuities, opening and closing of discontinuity gaps, and rotations of blocks are allowed.

Build models using improved automatic zone generation in fully deformable blocks, directly from closed geometry surfaces (e.g. DXF, VMRL, STL), by cutting blocks with DXF geometry, and Voronoi generation tools. Continuous and discontinuous joint patterns and discrete fracture networks (DFNs) can be generated on a statistical basis for discontinuities. 3DEC also contains two powerful, fully integrated scripting languages: FISH and Python. These expand modeling functionality by enabling your analysis to be parameterized and customized.


3DEC has been developed primarily for geotechnical engineering applications in the fields of civil and mining engineering and energy extraction. 3DEC is also a valuable tool used for research in rock mechanics, the stability of masonry structures, and the behavior of fractured systems. Although, through scripting and custom constitutive models, the possibilities are virtually limitless.


Options in 3DEC are sold separately from the general license, allowing users to select the program’s capabilities as meets their own analysis needs without having to purchase all features. Beginning with 3DEC Version 7, the Finite Element Structural Liners option is now included at no additional charge.

Dynamic Analysis: 3DEC simulates the nonlinear response of a system (soil, rock, and structures) to excitation from an external (e.g., seismic) source or internal (e.g. vibration or blasting) sources.

Thermal Analysis: The thermal option in 3DEC allows the simulation of transient heat conduction.

User-Defined Constitutive Models: User-defined constitutive models (UDMs) can be written in C++ for both deformable block materials (zones) and any discontinuities (joints, faults, bedding, artificial surfaces) to calculate new stresses, displacements and strains, for a modified existing material model or a fully customized material behavior.

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Latest News
  • 2019 Sloan Outstanding Paper Award Dr. Mojtaba Bahaaddini (Shahid Bahonar University of Kerman), along with Associate Professor Glenn Sharrock (Itasca/UQ),...
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  • Itasca Awarded Prestigious Caving 2040 Research Grant Itasca’s research aims to answer the key industry question “how should block caves be designed...
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6 Apr.
PFC Introductory Training-Minneapolis
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20 Apr.
3DEC and UDEC Introductory Training, Minneapolis
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12 Oct.
Focused Seismic and Liquefaction Training 2019
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