# Numerical Modeling & Analysis

Numerical modeling has been driven by a perceived need in recent times. It has led to large, clumsy and complex numerical models. This is not always because numerical modeling is an integral part of the design process, but sometimes because it is considered irresponsible to not bolster a design with plots of stress and displacement contours. Advanced numerical modeling is not a subject that lends itself to a research proposal, higher degree or paper publication. Properly performed numerical modeling will lead engineers to think about why they are building it – why build one model rather than another – and how the design can be improved and performed effectively.

TerraDol provides high end numerical modeling and analysis in Geotechnical and Tunneling field, specialized in Finite Element Analysis (FEM), Finite Difference Analysis (FDM), Discrete Element Analysis (DEM) and advanced Hydrocodes and Computational Fluid Dynamics (CFD).

• Rock Support Design / Rock Wedge Analysis
• Tunnel Stability Analysis
• Tunneling Induced Settlement Analysis
• Geological Frame Model
• Groundwater Flow Model and Seepage Analysis
• Fate & Transport Modeling
• Coupled Hydromechanical Analysis
• Blast Analysis
• Progressive Collapse Analysis
• Seismic Analysis
• Tunnel Ventilation & Evacuation Analysis

Continuum Analysis

FEM, FDM and BEM are continuum analysis methods, where the domain is assumed to be a homogeneous media. These methods are used extensively for analysis of underground structure’s stability problems. To account for the presence of discontinuities in a rock mass, mechanical and hydraulic properties of rock mass are reduced from those measured from intact samples. TerraDol utilizes FLAC, PHASES, PLAXIS, MIDAS GTS, SEEP/W, and MODFLOW for the continuum analysis.

Discrete Element Analysis

If the domain contains predominant weak planes and are continuous and oriented unfavorably to the underground structures, then a discrete element method (DEM) should be considered to understand behavior and stability of surrounding rock mass.

DEM permits a large deformation and finite strain analysis of an ensemble of deformable (or rigid) body (intact rock block), which interact through deformable, frictional contacts (rock joints). In hydraulic analysis, the DEM permits flow-networking analysis, which is suitable in ground water flow in jointed rock mass.

Coupled Hydromechanical Analysis

The coupled hydromechanical analysis is another powerful strength of DEM analysis because a flow in jointed rock mass is closely related with applied loading.  This type of analysis requires details of joint flow, aperture and disclosure relationships and is suitable only if dominating weak planes are well identified with their properly quantified properties. UDEC, 3DEC and HYDROBLOCKS are the most predominant programs.

3D Interactive Nonlinear Dynamic Analysis

3D interactive nonlinear dynamic analysis is considered for dynamic and thermal analysis including structural