Tunneling & Underground Structures
Design and construction
Preliminary design phase
During design of your tunnel, or underground structure, finite element analysis can help understand the inevitable risks to nearby structures – such as ground movement. This can be assessed at the planning state, but also as the project unfolds. The potential negative impact on safety and costs is mitigated by the ability to accurately predict issues before they happen.
A clear example would be that surface settlement caused by a shallow tunnel on a greenfield site could be predicted with some confidence, but the surface settlement in urban areas presents a much more complex interaction between the tunnel, its shafts, the ground and building above – diana provides the means to carry out a detailed 2d or 3d analysis of these interactions in one model and one command.
Monitoring and sustainability assessment
Service assessment phase
With a model imported into or designed in DIANA – you can predict the reaction of the structure following structural damage, freezing, fire, flood or earthquake, which is critical the safety and lifespan of the tunnel.
The model encompasses tunnel segments, joints, along with soil and grout pressures upon it, allowing all of the potential factors above to be analysed to show inherent deformations.
Dedicated features for the analysis of tunnels & underground structures
- In-situ Stress ( Ko procedure/gravity loading/pre-stress) and Pore-pressure Initialization
- Drained / Undrained Analysis
- Construction-staged analysis
- Seepage analysis (steady state / transient)
- Saturated or Partially saturated flow
- Consolidation analysis (full coupled stress-flow analysis)
- Pressure dependent degree of saturation
- Porosity or saturation dependent permeability
- Deformation dependent density and porosity
- Large displacement and large strain nonlinear analysis
- Special elements for nonlinear modeling of joints between the TBM lining segments
- Ground freezing analysis including latent heat consumption, thermal expansion and temperature dependent elasto-plasticity
- Generalized plane strain elements for 2D modeling of inclined tunnels or shafts in strongly anisotropic in-situ stresses
- Mesh-independent embedded bars and grids that allow easy modeling of:
- rock bolts, nails or geotextiles in solid soil elements
- reinforcement in beam or shell structural elements
- Soil-structure interaction with nonlinear behavior for both soil and structure
- Wide range of material models for the analysis of nonlinear concrete material behavior
- Transient nonlinear analysis for viscous behavior such as creep, shrinkage or swelling, ambient influence such as temperature or chemical concentration
- Young concrete analysis including hydration heat, shrinkage, hardening, visco-elasticity and cracking
- Higher order solid elements up to cubic interpolation
- Mohr-Coulomb, Tresca
- Drucker-Prager, Von Mises
- Transversely Isotropic
- Duncan-Chang
- Hoek-Brown
- Jointed Rock
- Modified Cam-Clay
- Jardine (London clay)
- Modified Mohr-Coulomb (Cap model)
- Special Interface Models
- User Supplied Subroutine
- Discrete cracking with interface elements
- Multi-directional
- Fixed crack model with strain decomposition
- Total-strain crack models with fixed and rotating cracks for tensile and compressive failure
- Fiber reinforced material models
- Creep and shrinkage models according to different international design codes
- Classic brick model for soil
- Eigenvalue analysis (eigenfrequencies, eigenmodes, participation factors, effective masses)
- Direct frequency response analysis
- Modal frequency response analysis
- Spectral response analysis (ABS, SRSS, and CQC modal combinations)
- Linear and nonlinear time domain analysis (total, transient and steady state, solution)
- Various time integration methods, e.g. Newmark,
- Wilson-theta, Runge-Kutta
- Hybrid Frequency-time domain analysis (steady state solution)
- Fluid-structure interaction
- Multi-directional base acceleration loads
- Prescribed nodal acceleration loads (release summer 2011)
- Distributed mass elements (2D line elements + 3D surface elements)
- Bounding/boundary elements for far field behavior (2D line elements + 3D surface elements)
- Viscous, structural, and continuous damping
- Specified or calculated initial conditions
- Consistent or lumped mass and/or damping matrices
- Towhata-Iai liquefaction model (2D models and largely undrained conditions)
- Nishi liquefaction model (for 2D/3D, partially drained conditions, arbitrary shearing direction)
- Bowl liquefaction model (for 2D/3D, partially drained conditions, horizontal shearing)
- User-supplied liquefaction models (USRLIQ subroutine)
Licensing packages
Choose your subscription
We provide a wide range of flexible licensing modules and subscription plans for advanced calculations. Our Sales Team are always more than happy to discuss your requirements and can make individualized proposals based on your specific needs.
