Conprehensive software for the elasto-plastic ground analysis and seepage analysis using Finite Element Method (FEM)


Initial Release:2016.06.09

limited to the seepage analysis
limited to the elasto-plastic ground analysis

Program Overview

Elasto-plastic ground analysis by using FEM (GeoFEAS) and steady/unsteady saturated - unsaturated seepage analysis (VGFlow) are available in this geometric value analysis program.
In this program, GeoFEAS and VGFlow running on the same platform share geometry data and mesh data. This decrease a large amount of work for creating analysis models, which were made on each platform in the previous individual products.
The solver of this product utilizes the ground analysis program developed by the laboratory of ground engineering, Department of Civil and Environmental Engineering of Gunma University. The Pre-Post processor is developed in-house and they are coupled together as a total solution.
*This is an integrated product, but each product can be used separately.

▲Sharing of geometry and mesh



Functions and Features

Creation of model geometry

Intersection creation

Intersections can be created between arbitrary objects like solid, surface, and line. even if many structures are intersected intricately.


In 3 dimensions, the number of objects becomes larger than that of 2 dimensions, and model editing becomes more difficult. Grouping of plural objects with the same property value makes it possible to select many objects in a lump and assign material constant.

Display/hiding and confined selection of objects

In the complex 3D model, only the object that you want to edit can be displayed. You can also make a selection from the each of the confined objects of materials, surfaces, and solids.

Import of the terrain data in the LandXML format

You can now import the 3 dimensional coordinate data and its connection information of the point clouds on the ground surface or on the stratum boundary created in LandXML format. Complex terrain information can be built automatically without manual entering, and object structure can also be modeled from the information.

▲Terrain created from LandXML file

▲Display/hiding and confined selection of objects

Realistic modeling of the objects like complex terrain and crossed tunnel that can be handled only by the 3 dimension analysis is also available.

Mesh division

Mesh is divided semiautomatically. First, set the number of divisions of block line. The line can be divided at regular intervals or in the specified ratio. Surface is parted into triangle or rectangle, and solid is parted into tetrahedron or pentahedron. Model mesh is parted easily even after the number of division has been changed.

Element library

Solid elements are used for the ground modeling. Tetrahedron, pentahedron, and hexahedron element are available in this product.

▲Solid elements (tetrahedron, hexahedron, and pentahedron)

Post processor

▲Contour figure and plane cut of that

About GeoFEAS

GeoFEAS3D is "Geotechnical Finite element Elastoplastic Analysis Software 3D". It is the software product for 3D stress-deformation analysis of soil under static conditions. This FEM product can be used for the elast-plastic analysis in a lot of ground related field such as a pile foundation analysis, earth retaining excavation analysis, tunneling shield, and slope stability analysis.

Applied for

  • Stress and deformation analysis of the ground
  • Slope stability analysis
  • Retaining excavation analysis
  • Analysis of the effect to the surrounding ground during the tunneling shield excavation
  • Tunnel construction study analysis in NATM method
  • Study of the effect of changes in the water pressure on the ground
  • Study of the interaction between ground and structure
  • Seismic response method

Functions and features

Stage analysis

Material constant, boundary conditions, and stress release rate during the excavation can be set for the each step of the stage analysis (construction step analysis).

Shear strength reduction method

At each analysis stage, you can calculate overall safety rate by shear strength reduction method and estimate the slip surface. The method can be applied to the 3 full elasto-plastic models.

Local safety rate

This is calculated for each integration point.

Combination of analysis functions

Using some analysis functions together, you can execute the deformation analysis and stability analysis at the same time for a variety of problems related to ground, such as excavation and embankment, and slope stability, support force.

Mixture of the constitutive law

This can be provided to each material.

Type of analysis

Static total stress analysis

Load conditions

This is a program that analyze total stress without regarding permeability phenomenon of the ground. Considering water pressure as nodal load, you can study the influence to the ground exerted by the change in water pressure.
As load types, you can consider node concentrated load, uniformly distributed load, distributed load, and volume load (own weight and static seismic).

Element catalog Structure models Support
Concentrated load Nodal concentrated load Yes
Distributed load Linear distributed load, plane distributed load Yes
Own weight Horizontal acceleration, vertical acceleration Yes
Distributed load Constant horizontal load in depth, constant vertical load in depth Yes
Horizontal seismic intensity distributed in depth,
vertical seismic intensity distributed in depth
Water pressure Water pressure on node Yes

Boundary conditions

single point constraint (horizontal roller, vertical roller, fixed, and pin), multi-point constraint (MPC, hinge), and forced displacement are available. Material constant and boundary condition can be set in each stage.

Constitutive law

The most basic method of stress-deformation behavior analysis of soil is using elasto-plastic analysis. It is necessary to select proper element types, constitutive laws, etc.
GeoFEAS Flow has 15 constitutive laws for soil and structure from the simplest linear elastic constitutive law to elasto-plastic constitutive law. No-tension material is also available. In the Processor, it is possible to perform both deformation and stability analysis at the same time by combining stage and SSR analysis, and to deal with a wide range of soil related problems such as filled/excavated area, slope stability and bearing capacity, etc.

Model types Structure models Note
Elastic (1) Linear elasticity Isotropic
(2) Laminated elasticity Anisotropic
Non elastic (3) D-min Technique by CRIEPI
Non-linear (4) HD (Hardin-Drnevich)
(5) RO (Ramberg-Osgood)
(6) UW-Clay (Ugai-Wakai)
Full elasto-plastic (7) MC (Morh-Coulomb) Associative/nonassociative flow rule
(8) DP (Drucker-Prager) Associative/nonassociative flow rule
(9) MC-DP (Mohr-Coulomb / Drucker-Prager) Nonassociative flow rule
Elaso-plastic (10) PZ-Sand (Pastor-Zienkiewicz)
(11) PZ-Clay (Pastor-Zienkiewicz)
No-Tension (12) Linear elasticity
(13) Laminated elasticity

You can apply bi-linear model to the bar element and the spring element, and Mohr-Coulomb method to the joint element. Linear elastic model can be applied to the beam, bar, spring, and joint element.

Output items

Result type Result
Contour figure Displacement
Max. shear stress
Increment of Max. shear stress
Compressive stress
Tensile stress
Local safety rate
Total safety rate (only for SSR analysis)
Tensor Solid element stress
Solid element strain
Section force of the plate element
bending moment of the plate element

About VGFlow

Saturated/unsaturated seepage analysis program using Finite Element Method (FEM).
It provides easy ways to generate two and three dimensional complicated shaped geological boundary models, and several functions such as regular meshing, auto-meshing and re-meshing by setting types and dimensions of elements.
Stationary and transient analysis can be conducted. It also supports various boundary conditions, and for unsaturated seepage characteristics, calculations can be made using the van-Genuchten model, which is a typical empirical formula, and by inputting test values such as moisture characteristic curves in a table, and has built-in parameters identified for typical ground in Japan. Various output functions, such as contour, isosurface and vector diagrams, enable wide range of verifications.

Applied for

  • Check of the rainfall influence against road banks
  • Influences of rainfall and spring in large basin
  • Measures of seepage surface and water pressure distribution in river levee
  • Design calculation of fill type dam body and investigation of seepage on the ground around reservoir
  • Examination of permeability in the basic process like curtain grouting
  • Design calculation of dam body of reservoir and one for disaster prevention
  • Examination of piping and boiling during excavation
  • Influences of confined groundwater
  • Effect of drainage well on pore pressure distribution in landslide region
  • Investigation of seepage in cofferdam

Functions and features

Type of analysis

Steady flow analysis / Transient flow analysis

Analysis model

3D flow model

Boundary conditions

This product can define the following seven types of boundary conditions and set fluctuating water level and rainfall boundaries at the same time.

  • Known hydraulic head
  • Known flow
  • Leaching
  • Outflow forbidden
  • Point source
  • Fluctuating water level
  • Rainfall

Unsaturated seepage characteristics

  1. van Genuchten model
  2. Volumetric water contents θ - Suction ψ, and Volumetric water contents θ - Relative hydraulic conductivity Kr

Library of the material parameter

This program includes the default value for 10 kinds of soil and the library of unsaturated seepage characteristics written on the guideline for structural examination of river embankment.

Output items

Result type Result
Contour figure  Pressure head
Pore water pressure
Fractional saturation
Volume water content
Hydraulic gradient
Current speed vector
Tensor Current speed vector

Enhancement of CIM function on the geotechnical analysis series products

Data linkage using terrain data file (*.GF1)
Geotechnical Finite element Elastoplastic Analysis Software (GeoFEAS)2D Ver.3

The amount of displacement imported to Flexible structure sluiceway design for further analysis
By importing results of ground deformation analysis (settlement / horizontal displacement distribution) to the "Flexible structure sluiceway design", the level2 seismic test for the longitudinal direction can be performed.
画像をクリックすると大きな画像が表示されます。 画像をクリックすると大きな画像が表示されます。
GeoFEAS2D Flexible structure sluiceway design

It can modelize only ground that a surrounding ground effect analysis is conducted in the Temporary sheathing work design. The ground deformation can be calculated by giving the wall displacement as the forced displacement. 
Dynamic effective stress analysis for ground (UWLC)

Acceleration rate imported to Slope stability analysis for further analysis
When applying the Newmark method to high embankments with a height of about 30 m or more, it is necessary to input the response acceleration waveform of the slip soil mass as the ground motion.
Data linkage between "Dynamic effective stress analysis for ground (UWLC)" and "Slope stability analysis" corresponds to the Newmark method analysis calculated by using the response acceleration waveform.
The level2 seismic stability calculation for high embankment and large embankment.
画像をクリックすると大きな画像が表示されます。 画像をクリックすると大きな画像が表示されます。
UWLC Slope stability analysis
2-D seepage analysis(VGFlow2D)

Water line data imported to GeoFEAS2D
画像をクリックすると大きな画像が表示されます。 画像をクリックすると大きな画像が表示されます。

Water level data imported to UWLC
Water line and potential line imported to Slope stability analysis
Saturated / unsaturated seepage FEM analysis results can be reflected by file linkage (*.PRS [water line], *.PTN [isopotential line]).
GeoFEAS VGFlow (limited to the seepage analysis)

Water level data imported to LEM3D
Analysis results computed with GeoFEAS VGFlow (limited to the seepage analysis) or third party's product can be imported to 3-D slope stability analysis(LEM). It creates underground water level required for landslide analysis and enables the 3D slope stability analysis.
画像をクリックすると大きな画像が表示されます。 画像をクリックすると大きな画像が表示されます。


Product Price

■Product Price



GeoFEAS VGFlow USD16,700
GeoFEAS VGFlow (limited to the seepage analysis) USD7,900
GeoFEAS VGFlow (limited to the elasto-plastic ground analysis) USD10,500

■Price of Floating License

Paying 40% of the product price allows anyone to use the product on any PC anywhere in the world.



GeoFEAS VGFlow USD6,680
GeoFEAS VGFlow (limited to the seepage analysis) USD3,160
GeoFEAS VGFlow (limited to the elasto-plastic ground analysis) USD4,200

>>Information of license type


Upgrade Price

Program Name Object Product Price/Category Note
GeoFEAS VGFlow GeoFEAS VGFlow (limited to the seepage analysis) USD10,560 Upgrade -
GeoFEAS VGFlow GeoFEAS VGFlow (limited to the elasto-plastic ground analysis) USD7,440 Upgrade -

Price of Subscription Service Contract

Price of Subscription Service Contract

■Support information
-Software upgrade   -Technical inquiry (Email, Tel)
-Download service   -Maintenance and update notifications via email

* We are sequentially making a transition from the maintenance-support service to [Subscription Service] from April 1, 2016 in order to enhance support for diverse product usage and to reduce license management cost.

Product Subscription cost
of first year
Subscription cost
of subsequent years
(annual cost)
Subscription (GeoFEAS VGFlow) Free USD6,680
Subscription (GeoFEAS VGFlow (limited to the seepage analysis)) USD3,160
Subscription (GeoFEAS VGFlow (limited to the elasto-plastic ground analysis)) USD4,200
Subscription (GeoFEAS VGFlow Floating) USD9,352
Subscription (GeoFEAS VGFlow (limited to the seepage analysis) Floating) USD4,424
Subscription (GeoFEAS VGFlow (limited to the elasto-plastic ground analysis) Floating) USD5,880

Academic Price

An Academic License can be provided for educational purposes and used by teachers, lecturers, academic researchers, and students.

Academic Price

Product Academic Price
GeoFEAS VGFlow USD13,360
GeoFEAS VGFlow (limited to the seepage analysis) USD6,320
GeoFEAS VGFlow (limited to the elasto-plastic ground analysis) USD8,400

Version Update History

Version Update History

■The version upgrade and revision upgrade (without charge) contents are listed as following.

Version Release date Update contents
1.0.0 16/06/09

New Release

Product Operation Environment

Product Operation Environment

OS Windows 10 / 11
CPU Environments that meet the system requirement of the OS and operate without any problems.
Required memory (including OS) Environments that meet the system requirement of the OS and operate without any problems.
Required disk capacity About 300MB or more for installation and a few GB for computing.
Display (image resolution) 1024×768 or greater is recommended.
Only [Small Font] font size is supported.
Input data extension Pre part input data (GF3)
File export Post part result data (rsv4)
Linkage with other programs <Import>
LandXML topography data file
DXF file
Vertex coordination (XML format)

Order / Contact Us

Order / Contact Us

■ Inquiry

Contact us from Sales inquiry or email to or

Sample screen

▲Import of terrain data of LandXML

▲Intersection in tunnel

Pile foundation


▲Examination of seepage in dam body

▲Examination of collecting well

▲Stress vector



▲Boundary condition

▲Max. strain stress

▲Section contour


▲Pore water pressure

▲Velocity vector


▲Input dialog of material characteristic
(seepage flow analysis)



▲Degree of saturation

▲Hydraulic gradient in z direction

▲Report output (GeoFEAS)

▲Report output (VGFlow)














 >> サポートページ Engineer's Studio® Q&A集