Solution for Geotechnical and
Foundations Analysis
The state-of-the-art technology for
the civil engineering world
Geotechnical module capabilities
•
•
•
•
•
•
•
•
•
Geotechnical properties library for soils and rocks
Superficial Foundations
Deep Foundations (Pile/micro pile cap)
Retaining wall generation and design (Sheet
Piles)
Underground structures (tunnels)
Slope stability analysis
Seepage analysis
Integration with FLAC3D™ (available in
CivilFEM®
INTRO)
Other Capabilities
Soils and Rock Library
•
•
•
Soil classification
according to Casagrande’s
“Unified Classification
System”
Library with mechanical, elastic and plastic
properties of typical soils and rocks (around
100)
Definition and use of properties not considered
by ANSYS® (Atterberg limits, Hoek & Brown
coefficients, etc.)
Correlations among geotechnical parameters
from tests or analysis (elasticity modulus
versus SPT, etc.)
Soils and Rock Library
•
Users can modify any material property
Soils and Rock Library
Properties used in a structural analysis with ANSYS®.
•
Multiple static or dynamic
properties are used, as
different densities depending
on water table level
•
Multiple
available
–
–
–
–
Plastic
Elastic
Drucker-Prager
Mohr-Coulomb
Cam-Clay
Behaviors
Soils and Rock Library
Most common
correlations
among properties.
CivilFEM database of
correlations. Users can
also define their own
correlations!
Soils and Rock Library – Integration with FLAC3D
•
Capabilities for 11 different constitutive
model types integrated in FLAC3D
Materials
Cap Drucker-Prager Model
•
Cap Drucker-Prager plasticity model applicable to
• Simulation granular materials such as soils
• Powder compaction simulation
• The model has also been used for modelling pressure-dependent
plasticity of polymers
•
Applicable to PLANE182-183 (except for plane stress) and SOLID185-187
•
The model is a new addition to the existing Extended Drucker-Prager
model (TB,EDP)
• Introduce cap for both tension and compression
• Include cap hardening
• Include shear envelope hardening
Materials
3D Mohr-Coulomb Model
Materials
3D Cam-Clay Model
Hoek-Brown Failure Criteria
•
Hoek & Brown parameters must be defined to
perform the analysis according to Hoek &
Brown.
•
They can be all modified by the user.
•
CivilFEM uses its own calculation routine to
simulate the behavior of rock foundations
following Hoek & Brown criteria.
Hoek-Brown Failure Criteria
Example of Hoek-Brown failure
criteria of a cylindrical hole
Terrain Initial Stress
•
The program automatically calculates the initial stress
state from the given topography and soil parameters. The
initial stresses are stored in an ASCII file

V


H
The created initial
stress file is
automatically
introduced into the
model using the
ISFILE command
of ANSYS
H
Superficial Foundations
•
Footing and continuous foundations:
• 2D/3D soil-structure interaction models
Superficial Foundations
•
Slab Foundations:
• 3D soil-structure interaction models
• 3D Soil foundation stiffness models with calculation of
precise, average, maximum and minimum values
Layered Soil Generation
•
Automatic generation of equivalent geometrical models of
layered soils.
Utility:
Ballast module
calculation and
retaining walls.
It takes into account the
influence of water level
W
h
Definition of each
layer property
Soil Foundation Stiffness
•
Obtaining the theoretical value of the the soil foundation
stiffness, by means of the Winkler model, according to the
foundation geometry and earth properties.
It allows obtaining
the theoretical value
of the ballast module
for any foundation or
earth configuration
(including those
within stratum).
Ballast module distribution
at each foundation point
Soil Foundation Stiffness
The soil foundation
stiffness distribution
for different
configurations of
foundations
Soil Foundation Stiffness
•
•
•
•
The earth layers may be generated using the capability of
soil generation.
The soil foundation stiffness (ballast module) value allows
approximating the soil elastic behavior (E, ). Its use avoids
the necessity of modeling the earth underneath the
structure.
Furthermore, it may be obtained not only the precise value
for each point but also the average, maximum and minimum
values of the module throughout foundation.
The soil foundation stiffness values calculated by CivilFEM
are automatically send to ANSYS for the following
superstructure calculations with beams shells or solid
elements.
Deep Foundations
•
Pile Cap Wizard:
• Automatic generation of rectangular, polygonal or
circular pile groups
Deep Foundations
•
Pile Cap Wizard:
• Pre-Design of the Pile length
Deep Foundations
•
Pile Cap Wizard:
• Automatic calculation of the reinforcement amount
required according to the selected code (punching,
primary and secondary reinforcement of both sides for
rigid and non-rigid pile caps)
Deep Foundation
Pile Wailing Load Test
Load Test Reinforcement
Design
Micro-piles
•
Extending the Geotechnical Module capabilities, CivilFEM with
ANSYS incorporates a specific design and calculation tool for
micropile foundations.
•
This utility is added to the
already existing pile cap
wizards, which cover most
of the deep foundations
designs.
Retaining Wall Calculation
•
The terrain definition is done using the CivilFEM capability of
terrain creation.
•
The remaining needed data then now input using a new wizard.
•
Three different calculation types are possible:
• Beam model
terrain.
, using spring elements for simulating the
• Plane strain model
• 3D solid model Perpendicular
calculated.
retaining walls can be
Retaining Wall Calculation
•
Calculation of 2D (automatic wizard) or 3D Sheet Piles
• Non-linear construction sequence analysis
• One or two sheet piles can be analysed simultaneously
taking into account anchors, water level, layered soils,
applied loads.
The excavation or
backfilling process
can be visualized in
each calculation
step.
Retaining Wall Calculation
•
•
•
•
1
Systems generated may consist of one or two screens that can
be integrated inside other ANSYS models like a subset.
The model is solved by means of an evolutionary calculation, in
which each calculation stage represents a step in excavation or
backfill.
The reinforcement of the retaining walls can be later designed
by CivilFEM.
Allowing any CivilFEM
cross section.
ANSYS 9.0
MAR
2 2005
17:12:45
LINE STRESS
STEP=20
SUB =1
TIME=20
CFETAB_ICFETAB_J
MIN =0
ELEM=161
MAX =2.494
ELEM=133
0
.277056
.554113
.831169
1.108
1.385
1.662
1.939
2.216
2.494
Retaining Wall Calculation
•
Terrain definition from soil materials.
2D - Retaining Wall Calculation
OPTION 1:
•
•
•
CivilFEM performs retaining wall calculation using
non-linear and evolving finite element models considering the
changing with excavation level
SSI: modeled with non- linear springs + contact elements
Retaining wall >1 1/2 D
It takes into account
The wall may be
considered as a
non-linear structure
and analyzed by the
non-linear module of
CivilFEM
the soil-structure
interaction using
non-linear springs
with contact
elements
2D - Retaining Wall Calculation
•
Using the new wizard, both the geometry and the excavation
stages are defined.
2D - Retaining Wall Calculation
OPTION 2:
• The model approach is the following: plane strain, simulated with a
beam being one meter width.
Element types
supported
2D - Retaining Wall Calculation
•
The terrain for the model is imported from the previously defined
one
The terrain may have
any inclination.
2D - Retaining Wall Calculation
•
•
A 2D plane strain model is created.
Anchorages are modeled as link elements.
2D - Retaining Wall Calculation
•
Calculation of 2D (automatic wizard) or 3D Sheet Piles
• With any CivilFEM cross section
• Interaction with other structures
3D - Retaining Wall Calculation
OPTION 3:
• Definition of a 3D retaining wall uses the same wizard as the
plane strain model.
• Geometry definition changes and therefore the longitudinal
geometry of the retaining wall must be defined.
3D - Retaining Wall Calculation
•
In plane strain and 3D models, the initial stress of the terrain can
be calculated and entered in the model as phase 0, previously to
the general analysis.
s
V
s
s
H
H
3D - Retaining Wall Calculation
•
Any geometry and any terrain for the excavation can be modeled.
3D - Retaining Wall Calculation
•
Any geometry and any terrain for the excavation can be
modeled.
3D - Retaining Wall Calculation
•
Analysis of Retaining walls made of piles
Civil FEM
3D Retaining wall management by CivilFEM (Piles)
Anchorage
Piles
Piles
Offset
Offset=0
Anchorage support beam
Anchorage support beam
X
X
Different types of anchorages supports
X
X
3D - Retaining Wall Calculation
•
A 3D solid model is created.
Phase 7
1
Y
Z
X
Earth Pressures
Automatic earth pressures on FEM Models:
•
•
•
•
Dry and flooded earth
Active, Passive and at rest pressures
Pressures due to the earth weight and overload
Earth pressure for beam, shell or solid elements
1
1
Y
Y
Z
X
Z
X
Underground Structures (Tunnels)
•
•
•
•
Terrain Initial Stress
Hoek & Brown Failure Criteria (rocks)
Plastic Constitutive models: 2D/3D Drucker-Prager, MohrCoulomb and Cam-Clay
Element Birth and Death capability (non-linear construction
sequence analysis)
Wizard for Tunnels design
Tunnel section
PLOT NO.
1
-909.174
-878.511
-847.848
-817.185
-786.522
-755.859
-725.196
-694.533
-663.87
-633.207
Te n sió n ve
rtic a l.Tunnel
Fre n te Advancement
d e a va n c e
Vertical
Stress.
Longitudinal
Section
Forces and Moments on Concrete
COL
3
COL
1
COL
2
Forces acting on
concrete tunnel
PLOT NO.
1
-.018494
-.014481
-.010468
-.006455
-.002443
.00157
.005583
.009596
.013609
.017621
MVertical
o vim ieMovement.
n to ve rtic aTunnel
l. Fre n te
d e a va n c e
Advancement
Longitudinal
Section
Wizard for Tunnels design
Wizard for Tunnels design
Wizard for Tunnels design
And easier….
…several section types
Wizard for Tunnels design
And excavation types
Underground Structures (Tunnels)
•
Element Birth and Death capability (non-linear construction
sequence analysis)
Underground Structures (Tunnels)
•
Plastic Constitutive models: 2D/3D Drucker-Prager, MohrCoulomb, Cam-clay
Underground Structures (Tunnels)
•
Phases
Slope Stability (Classic Methods/FEM)
Polygonal for Janbu
Method
G e n e ra c ió n d e fa m ilia s d e p o lig o n a le s
y 11
Grid of centers defined
by the user.
Grid of centers for the
Fellenius or Bishop
G e n e ra c ió n d e fa m ilia s d e c írc u lo s
y12
y
•
CivilFEM allows to calculate the safety
factor against sliding phenomena in 2D
models defined in ANSYS using Fellenius,
Bishop, Morgestern-Price, U.S. Corps of
Engineers or Janbu methods.
The user may also solve the model by
finite elements and obtain the safety factor.

•
(x o ,yo )
x1
(x 11 ,y11)
(v
(x 1 2 ,y1 2)
x
y21
,v
y
)

x
y51
R
y22
x2
(x 2 2 ,y2 2)
y52
x5
(x 2 1 ,y2 1)
y
F
Slope Stability (Classic Methods/FEM)
•
Very easy and intuitive way of defining the slope, circles,
polygons, water pressures lines, seismic action and so on.
Slope Stability
•
With just one calculation, it’s possible to visualize the results
according to the different available methods.
Reinforced Soil
•
•
•
This reinforcement can be used to simulate:
• Sheet or grid reinforcement
• Strip reinforcement
• Soil Nails
• Reinforced slopes or Reinforced Soil walls
CivilFEM will also help to design the reinforcement needed, by
calculating if the maximum strength is reached or not.
The common wedge sliding surface (more appropriate for this
type of models) can be defined, although the generic polygonal
or circular sliding surfaces are also available.
Seepage Analysis
•
•
•
Calculating hydraulic heads and pore water pressures
Obtaining the saturation line for 2D problems
Exporting the obtained pore water pressure for slope stability
analysis. The finite element mesh used in both analyses may be
different
Seepage Analysis
MN
0
3 .3 3 3
6 .6 6 7
10
1 3 .3 3 3
1 6 .6 6 7
20
2 3 .3 3 3
2 6 .6 6 7
30
0
3.333
6.667
10
13.333
16.667
20
23.333
26.667
30
Some Other Capabilities
•
•
•
•
•
•
•
Automatic Load Stepping to select suitable load increments
Large strains calculations to perform significant changes in the
geometry
Plastic Constitutive models: 2D/3D Drucker-Prager and 2D Mohr
Coulomb (plain strain), Cam-clay, viscoplasticity, viscoelasticity,
anisotropic plasticity, etc.
Safety factors defined as the ratio of the failure load compared to
the working load.
Powerful Post-processor: deformation, stresses, forces,
reinforcement amounts, etc
2D/3D Dynamic compaction, using the cycling loads
Soils Improvement: Birth and Death of elements features for jet
grouting, gravel column.
Geotechnical and Foundations Module