This lesson illustrates the use of PLAXIS for the analysis of submerged construction of an excavation. Most of the program features that were used in the previous chapter will be utilised here again. In addition, some new features will be used, such as the use of interfaces and anchor elements, the generation of water pressures and the use of multiple calculation phases. The new features will be described in full detail, whereas the features that were treated in the previous lesson will be described in less detail. Therefore it is suggested that the previous lesson should be completed before attempting this exercise.

This tutorial concerns the construction of an excavation close to a river. The excavation is carried out in order to construct a tunnel by the installation of prefabricated tunnel segments. The excavation is 30 m wide and the final depth is 20 m. It extends in longitudinal direction for a large distance, so that a plane strain model is applicable. The sides of the excavation are supported by 30 m long diaphragm walls, which are braced by horizontal struts at an interval of 5.0 m.

In order to inspect the calculation results, please calculate the Plaxis project: the results are not included to miminimisehe download size.

The post 2D Tutorial 02: Submerged construction of an excavation appeared first on Plaxis.

In this lesson, a first application is considered, namely the settlement of a circular foundation footing on sand. This is the first step in becoming familiar with the practical use of PLAXIS 2D. The general procedures for the creation of a geometry model, the generation of a finite element mesh, the execution of a finite element calculation and the evaluation of the output results are described here in detail. The information provided in this lesson will be utilised in the later lessons. Therefore, it is important to complete this first lesson before attempting any further tutorial examples.

A circular footing with a radius of 1.0 m is placed on a sand layer of 4.0 m thickness as shown in Figure 1.1. Under the sand layer, there is a stiff rock layer that extends to a large depth. The purpose of the exercise is to find the displacements and stresses in the soil caused by the load applied to the footing.

The post 2D Tutorial 01: Settlement of a circular footing on sand appeared first on Plaxis.

Triangulated soil surfaces usually contain a lot of irrelevant details for the intended analysis. This movies explain how to convert triangulated surface to smoothed NURBS surfaces for efficient modelling in PLAXIS.

The post Converting triangulated surfaces for efficient modelling in PLAXIS 3D appeared first on Plaxis.

The PLAXIS  2D to 3D Converter takes the 2D model geometry and soil properties and will convert this as an extruded model in PLAXIS 3D. This movie shows how to install and run the tool.

Installation and launch instructions:

• Extract the Conversion Tool files to \pytools\input\ in the PLAXIS 2D 2017 installation directory:
• Start PLAXIS 2D 2017.00 with your model, activate the remote scripting server
• Start PLAXIS 3D 2016.02 and start the remote scripting server
• From the Expert menu in PLAXIS 2D 2017.00 select the Python submenu, then Run script -> Open
• Navigate to -> \pytools\input\ and select conversion_runner
• The Conversion Tool launches and automatically connects to PLAXIS 2D and 3D
• After running the Conversion tool the first time, you can find it in the Run script submenu as well

The post Using the PLAXIS 2D to 3D Converter appeared first on Plaxis.

In recent years, the embedded pile model has been successfully implemented in PLAXIS 3D. The embedded pile consists of beam elements connecting to the surrounding soil by means of special interfaces (skin interface and foot interface). Although the embedded pile doesn’t take into account volume, a particular elastic region around the pile whose dimension is equivalent to the pile diameter is assumed in which plastic behavior is neglected. This makes the embedded pile almost behave like the volume pile. Therefore, it may be said that the embedded pile model is considered as a ‘simplified’ model of the volume pile. Although the embedded pile is a relatively new feature, it has been validated by comparisons with the volume pile as well as with measurements from real tests. The finding shows that the embedded pile is not only in good agreement with the volume pile, but also able to resemble the real pile behavior. However, these validations are only considered in terms of axial loading (compression loading and tension loading). Therefore it’s questionable whether the embedded pile also shows a good performance in the situation of being subjected to lateral loading.

In order to answer this question, this thesis is aimed to give a validation of the embedded pile for lateral loading caused by external forces as well as soil movements in embankment applications. This validation is firstly made in PLAXIS imaginary models (a ‘simplified’ model as considered in Chapter 3 and ‘advanced’ models as considered in Chapter 4) and then in a PLAXIS model of a real case study as considered in Chapter 5.

The post Validation of PLAXIS Embedded Piles For Lateral Loading appeared first on Plaxis.

The Thermosyphon boundary option will be removed from the next update pack (PLAXIS 2D 2017.01) and it will be reintroduced once validations and more detailed documentation become available.

We are working on a solution for this.

The post Thermosyphon boundary option should be avoided in 2D 2016/2D 2017 appeared first on Plaxis.

The new PLAXIS 2D 2017 version has several new features. One of them is permeability in interfaces. In previous versions, interface elements could be either impermeable or fully permeable in groundwater flow, consolidation and fully coupled flow-deformation analyses. This allows for blocking the flow through walls, plates or tunnel linings since plates by themselves are fully permeable in PLAXIS. However, several applications may require semi-permeable interfaces that allow for some water to pass the structure. Moreover, interfaces may also contribute to groundwater flow in the interface longitudinal (parallel) direction. In this way, they act as ‘drains’ with a certain drainage capacity.

Hydraulic properties of interfaces

The hydraulic conductivity or resistance of interfaces is not only defined by permeability, but also by the ‘thickness’ of the structure or the soil-structure interaction zone. However, this ‘thickness’ is not always a well-defined quantity. Therefore, the hydraulic properties of interfaces are defined by two quantities that have a well-defined meaning:

• Hydraulic resistance: to define the hydraulic conductivity across the interface or structure
• Drainage conductivity: to define the hydraulic conductivity in the interface longitudinal direction

Figure 1. Interface permeability parameters: left hydraulic conductivity across
the interface (d/k) for flow normal to the interface, right: hydraulic conductivity
in the interface longitudinal direction (d·k) for flow parallel to the interface.

Considering a semi-permeable wall with a thickness d and permeability k, the hydraulic resistance is defined by d/k, expressed in the unit of time. Considering Darcy’s law, q = k dφ/dl, where k is the cross permeability and dφ/dl is the gradient of the groundwater head across the wall, which is the difference between the groundwater head left and right of the wall over the wall thickness (Δφ/d). Hence, for a given hydraulic resistance d/k, the specific discharge q = k Δφ/d = Δφ/ (d/k). In order to determine d/k, one needs to measure the average discharge q through a wall (per unit of area) for a given head difference Δφ, so d/k = Δφ / q

Considering a semi-permeable gap with a thickness d and permeability k between two impermeable media, the drainage conductivity is defined by the product of d and k (d·k), expressed in the unit of volume per unit of time per unit of width in the out-of-plane direction. This quantity defines the total amount of water that is transported through the gap (drain) per unit of time per unit width. Considering Darcy’s law, as listed above, the gradient is now defined by the difference in groundwater head over the length of the gap (in longitudinal direction) divided by the gap length, such that q = k Δφ / L. The total amount of water Q is q times the thickness d times the unit width b, where b = 1 length unit for a plane strain application, so Q/b = d k Δφ / L. In order to determine d·k, one needs to measure the total discharge Q/b through the gap (per unit of width in the out-of-plane direction) for a given head difference Δφ and a given length of the gap L, such that d·k = Q/b * L / Δφ.

Note that, neither for the hydraulic resistance nor for the drainage conductivity, the actual thickness d and permeability k really matter.

The post Permeability in interfaces appeared first on Plaxis.

When modelling semi-permeable or impermeable structures like retaining walls or tunnel linings, the permeability of such a structure is not controlled by the structure itself, but by the interfaces surrounding it. These interfaces, when active in flow, can be defined as fully permeable, impermeable, or semi-permeable. This article shows situations and considerations when modelling semi-permeable structures like retaining walls or tunnels using semi-permeable interfaces.

Practical case: retaining wall

In practical cases, one often has interface elements at both sides of a wall: for example, in the case of an excavation where the wall is, to some extent, permeable. When using the semi-permeable interfaces at both sides of the retaining wall, the hydraulic resistance for both interfaces will be taken into account (i.e. summed).

In such a case it is suggested to:

• assign the correct interface permeability to the ‘outside’ (soil side) of the wall
• whereas the interface at the ‘inside’ (the side that is excavated) is made fully permeable, even along the embedded part of the wall below the excavation.

This will ensure that the retaining structure's hydraulic resistance will not change during (multiple) excavation stages.

This can be done in two ways: a specific material dataset or deactivating the interface for flow.

Option 1: specific material dataset

One way to set this "inside" interface to fully permeable is by defining a specific material dataset and setting the Cross permeability of the interface to Fully permeable:

Figure 1. Setting Cross permeability to Fully permeable

To create this specific dataset:

1. you can make a copy of the "outside" interface material dataset (or the one from the adjacent soil);
2. and then only change the value for the cross permeability in this copy of the material dataset;
3. then, in your Staged Construction phases, you should apply this specific material dataset to the “inside” interfaces.

This implies you need to create a specific material dataset for each soil material in which the plate is embedded.

Option 2: flow conditions option: set inactive

When an interface is set to inactive for flow, it will act as if it is not there, and water can flow across this inactive interface without any resistance. Instead of setting a specific material dataset to the "inside" interface, we can now set the inside "Active in flow" state to inactive (uncheck the checkbox), while we keep the "outside" interface "Active in flow" checked.

Note that this setting is independent of the general active state for interfaces which are used for the deformation analysis:

Figure 2. PositiveInterface_1_1 set to Inactive for flow to behave as fully permeable while the interface state for deformation is set to Active.

We can also easily inspect this configuration visually: when we are in Flow conditions mode, we see the interfaces (Figure 3):

• Drawn in Orange when Active in flow is checked (interface is active for flow)
• Drawn in Grey when Active in flow is unchecked (interface is inactive for flow)

Figure 3. Outside interface (in this case Negative interface) set to active in flow,
and is drawn in orange and inside interface (in this case Positive interface) set to
inactive and is drawn in grey

This setting should then be explicitly checked for your phases.

Tunnel lining

Similarly for a semi-permeable tunnel lining: the correct interface permeability should be given to the interface on the outside of the tunnel lining, whereas the interface at the inside (which will be excavated) should be modelled as fully permeable.

Both approaches mentioned above can be applied here, too.

The post Permeability in interfaces: Practical situations appeared first on Plaxis.

For the case of semi-permeable interfaces, the output program shows the resulting specific groundwater flow through the interface elements (q_n for 2D, Q₁ for 3D).

These output results and their plots are not available in the case of fully impermeable or fully permeable interface elements.

Specifically, in the case of fully permeable interface elements, the pore pressure degrees of freedom are fully coupled in the calculation kernel. Since the nodes of the interfaces are fully coupled there is no difference in head and as a result, Darcy's law is not applied and the specific groundwater flow cannot be calculated.

Workaround

A workaround for this specific case it is to specify a very low value for the hydraulic resistance (d/k) for the interface cross permeability.

Video

This movies shows how apply the cross and parallel permeability options for interfaces and where to inspect the relevant results.

The post Output of flow results through interfaces appeared first on Plaxis.

When using boreholes in PLAXIS to define soil layers, Plaxis automatically creates soil polygons (2D) and soil volumes (3D) for these soil layers. When assigning materials to these soils, normally you would use a command in PLAXIS 2D like this:

setmaterial Polygon_1.Soil Sand

g_i.setmaterial(g_i.Polygon_1.Soil, g_i.Sand)

or

set Polygon_1.Soil.Material Sand

g_i.Polygon_1.Soil.Material = g_i.Sand

However, any soil layer might consist of any number of soil polygons, depending on the soil layer configuration (e.g. when a soil layer has zero thickness).
For this, you can also assign the material to the Soillayer objects. The Soillayers object is a listable that is updated after any change to the borehole soil layer settings and lists the Soillayer objects top-down.

0010> echo Soillayers
    SoilLayerList named "Soillayers"
    Count: 5
    0/-5. Soillayer named "Soillayer_1"
    1/-4. Soillayer named "Soillayer_2"
    2/-3. Soillayer named "Soillayer_3"
    3/-2. Soillayer named "Soillayer_4"
    4/-1. Soillayer named "Soillayer_5"
    

To assign a new material to a newly added soil layer (not an inserted soil layer) you can use:

setmaterial Soillayers[-1] Sand

g_i.setmaterial(g_i.Soillayers[-1], g_i.Sand)

For more complex geometries, you can for example do this:

1. Create a borehole
2. Add all soil layers
3. Then assign soil materials to each layer top-down

Example commands in PLAXIS 2D

borehole 0
soillayer 1  # add a soil layer with 1 m thickness 
soillayer 1
soillayer 1
soillayer 1
soillayer 1
set Soillayer_1.Soil.Material SoilMat_1  # assign material to the top soil layer 
set Soillayer_2.Soil.Material SoilMat_2  # assign material to the second layer 
set Soillayer_3.Soil.Material SoilMat_3  # assign material to the third layer 
set Soillayer_4.Soil.Material SoilMat_4  # assign material to the fourth layer 
set Soillayer_5.Soil.Material SoilMat_5  # assign material to the fifth and final layer 

Python solution

g_i.borehole(0)
# add soil layers, each 1 m thick:
g_i.soillayer(1)
g_i.soillayer(1)
g_i.soillayer(1)
g_i.soillayer(1)
g_i.soillayer(1)
# assign materials to the current configured soil layers
g_i.Soillayers[0].Soil.Material = g_i.SoilMat_1
g_i.Soillayers[1].Soil.Material = g_i.SoilMat_2
g_i.Soillayers[2].Soil.Material = g_i.SoilMat_3
g_i.Soillayers[3].Soil.Material = g_i.SoilMat_4
g_i.Soillayers[4].Soil.Material = g_i.SoilMat_5

This Python script can also be nicely written as:

g_i.borehole(0)
# add soil layers, each 1 m thick:
for i in range(5):
     g_i.soillayer(1)
# material list:
materials = [g_i.SoilMat_1,
             g_i.SoilMat_2,
             g_i.SoilMat_3,
             g_i.SoilMat_4,
             g_i.SoilMat_5]
# assign materials to the current configured soil layers
for layer, material in zip(g_i.Soillayers, materials):
    layer.Soil.Material = material

Version

The above examples are made with PLAXIS 2D 2017.00 using Python 3.4.x.

The post Soil layer material assignment using Python appeared first on Plaxis.

The staged construction settings and values for any Intrinsic properties of all UserFeatures (e.g. a load value for a line load, or a material assignment for a soil) are stored as a listable object per phase.

Material assignment

For instance, if you want to get the material assignment of a Soil_1_1 element in Phase_3, you can get the material object, and show the material name using these Python lines:

material = g_i.Soil_1_1.Material[g_i.Phase_3]
print(material.Name.value)

Or, if you want to just show all material assignments for all soil objects:

for phase in g_i.Phases[:]:
    for soil in g_i.Soils[:]:
        print("{} in {}: {}".format(
            soil.Name.value,
            phase.Name.value,
            soil.Material[phase].Name.value
            )
        )

Active state

You can use the Active property of a soil get to know if it is active or not in a phase:

active_state = g_i.Soil_1_1.Active[g_i.Phase_3] # True of False

To get a complete overview:

phase = g_i.Phase_3
for soil in g_i.Soils[:]:
    print("{} in {}: {} and Active={}".format(
        soil.Name.value,
        phase.Name.value,
        soil.Material[phase].Name.value,
        soil.Active[phase]
        )
    )

Setting a value

To set a value for a staged construction setting, we can use this too. To set the vertical component of a point load Fy in Phase_3, you can use this:

g_i.PointLoad_1_1.Fy[g_i.Phase_3] = -10

General mapping Staged Construction parameters

For most Intrinsic Properties you can just follow the Selection Explorer:

Then you can use this:

g_i.Soil_1_1.Active[g_i.Phase_3] # gives boolean of active state of soil object for Phase_3
g_i.Soil_1_1.Material[g_i.Phase_3] # gives assigned material object for Phase_3
g_i.Soil_1_1.ApplyStrengthReduction[g_i.Phase_3] # gives boolean for Phase_3
g_i.Soil_1_1.WaterConditions # this is a UserFeature of the Soil object for water conditions 
g_i.Soil_1_1.WaterConditions.Active[g_i.Phase_3] # gives boolean if water is active for Phase_3
g_i.Soil_1_1.WaterConditions.Conditions[g_i.Phase_3] # gives number of water conditions option for Phase_3. E.g. value is 0, means global water level

Version

The above examples are made with PLAXIS 2D 2017.00 and PLAXIS 3D 2016.02 using Python 3.4.x.

The post Access to Staged Construction settings using Python appeared first on Plaxis.

In each borehole, the information is stored for the different soil layers and their height. The Python script below returns a list of dictionaries with the relevant info: the soil layer's name, top, bottomand thickness.
The Soillayers will be sorted top-down.

import re

def get_borehole_layers(borehole):
    results = []
    for line in borehole.echo().splitlines():
        # Try to match something like:
        # "Layer 4: From -19 to -21 (thickness = 2)"
        m = re.search('(Layer .*): From (.*) to (.*) \(thickness = (.*)\)',
                      line)
        if m is not None:
            results.append({'name': m.group(1),
                            'top': float(m.group(2)),
                            'bottom': float(m.group(3)),
                            'thickness': float(m.group(4))})
    return results


# for a model with at least two soil layers
print(get_borehole_layers(g_i.Borehole_1)[1]) # prints the dict
print(get_borehole_layers(g_i.Borehole_1)[1]["top"]) # prints the top level value

The script uses the re module for regular expressions.

Version

The above examples are made with PLAXIS 2D 2017.00 and PLAXIS 3D 2016.02 using Python 3.4.x.

The post Retrieving soil layer info from boreholes using Python appeared first on Plaxis.

The PLAXIS Viewers are standalone programs and offer you and your clients the ability to view calculated PLAXIS 2D and PLAXIS 3D projects without the need of a licence.

The PLAXIS Viewer is part of your PLAXIS installation starting PLAXIS 2D 2016 and PLAXIS 3D AE.02. You will find the newest version of the PLAXIS Viewer in your installation directory (when you have installed the software). The Viewer works as a standalone application, so it can be copied to other locations or sent to your clients.

The PLAXIS Viewer can also be obtained by selecting the appropriate version and downloading it via these links below:

The post Plaxis Viewer – standalone program to view results appeared first on Plaxis.

New and improved features PLAXIS 3D 2017.00

• support for non-linear geogrid Elastoplastic (N-epsilon) type
• support for time-dependent geogrid Visco-elastic type
• possibility to define mesh element dimension in length units
• added multiply command for features and numeric properties
• support for unlimited number of points for curves in Output
• support for cross and parallel permeabilities
• support for encrypting the communications between a PLAXIS application and the scripting facilities
• dynamically loaded rigid bodies
• model explorer groups clusters based on material assignment in Output
• distance measurements dialog in Output displays additional information, such as rotation and tilt
• export geometry to step and dxf
• added more copy options for the command line session editor
• added PyQtGraph package to the Python distribution
• added Robertson type of CPT data interpretation
• added elasto plasticity of plates and beams
• added UBC3D-PLM soil model
• added a revolve tool for creating rotationally symmetric objects
• added creating nurbs curve from a point cloud
• performance improvements in the scripting layer
• extrude command behaviour changed - the profile is not moved to the trajectory any more but is extruded in place
• tunnel designer supports sequencing for NATM tunnels
• added functionality in tunnel designer to create subsection curves from existing curve endpoints in the visualization of the tunnel cross-section
• improved caching of Python client which fixed the "freeze on auto-complete" problem that was happening on some REPL environments
• added a preprocessing tool for Hoek-Brown parameters
• cross-sections made in Output now respond to visibility changes done in the model explorer
• the force envelopes of plates, beams and embedded beams can now be viewed and gathered in Output
• the foot forces of embedded beams can now be viewed and gathered in Output

In addition a large number of issues have been addressed.

For the latest information on known issues, and compatibility notes, please visit the Knowledge Base on the Plaxis website: https:/www.plaxis.com/support

CodeMeter firmware and drivers

The minimal required Codemeter firmware and driver version are, respectively, versions 1.18 and 6.00. The driver version provided with PLAXIS 3D 2017 is 6.40. Plaxis recommends to always use the latest versions.

The post PLAXIS 3D 2017.00 appeared first on Plaxis.

This example demonstrates the natural frequency of a long five-storey building when subjected to free vibration and earthquake loading.

The building consists of 5 floors and a basement. It is 10 m wide and 17 m high including the basement. The total height from the ground level is 5 x 3 m = 15 m and the basement is 2 m deep. A value of 5 kN/m² is taken as the weight of the floors and the walls. The building is constructed on a clay layer of 15 m depth underlayed by a deep sand layer. In the model, 25 m of the sand layer will be considered.

This requires the Dynamics module.

The attached *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 08: Free vibration and earthquake analysis of a building appeared first on Plaxis.

In this tutorial the influence of a vibrating source on its surrounding soil is studied. To reduce the calculation time, only one-quarter of the overall geometry is modelled, using symmetry boundary conditions along the lines of symmetry. The physical damping due to the viscous effects is taken into consideration via Rayleigh damping. Also, due to radial wave propagation, 'geometric damping' can be significant in attenuating the vibration.

The modelling of the boundaries is one of the key points in the dynamic calculation. In order to avoid spurious wave reflections at the model boundaries (which do not exist in reality), special conditions have to be applied in order to absorb waves reaching the boundaries.

This requires the Dynamics module.

The attached *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 07: Dynamic analysis of a generator on an elastic foundation appeared first on Plaxis.

This example concerns the stability of a reservoir dam under conditions of drawdown. Fast reduction of the reservoir level may lead to instability of the dam due to high pore water pressures that remain inside the dam. The dam to be considered is 30 m high. The top width and the base width of the dam are 5 m and 172.5 m respectively. The dam consists of a clay core with a well graded fill at both sides. The geometry of the dam is depicted in the image below. The normal water level behind the dam is 25 m high. A situation is considered where the water level drops 20 m. The normal phreatic level at the right hand side of the dam is 10 m below ground surface. The sub-soil consists of overconsolidated silty sand.

This requires the PlaxFlow module in order to be able to perform (transient) groundwater flow calculations.

The attached *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 06: Rapid drawdown analysis appeared first on Plaxis.

The lining of a shield tunnel is often constructed using prefabricated concrete ring segments, which are bolted together within the tunnel boring machine to form the tunnel lining. During the erection of the tunnel lining the tunnel boring machine (TBM) remains stationary. Once a tunnel lining ring has been fully erected, excavation is resumed, until enough soil has been excavated to erect the next lining ring. As a result, the construction
process can be divided in construction stages with a length of a tunnel ring, often about 1.5 m long. In each of these stages the same steps are repeated over and over again.

In order to model this, a geometry consisting of slices each 1.5 m long can be used. The calculation consists of a number of Plastic phases, each of which models the same parts of the excavation process: the support pressure at the tunnel face needed to prevent active failure at the face, the conical shape of the TBM shield, the excavation of the soil and pore water within the TBM, the installation of the tunnel lining and the grouting of the gap between the soil and the newly installed lining. In each phase the input for the calculation phase is identical, except for its location, which will be shifted by 1.5 m each phase.

The attached *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 05: Phased excavation of a shield tunnel appeared first on Plaxis.

The construction of an embankment on soft soil with a high groundwater level leads to an increase in pore pressure. As a result of this undrained behaviour, the effective stress remains low and intermediate consolidation periods have to be adopted in order to construct the embankment safely. During consolidation the excess pore pressures dissipate so that the soil can obtain the necessary shear strength to continue the construction process.

This tutorial concerns the construction of a road embankment in which the mechanism described above is analysed in detail. In the analysis two new calculation options are introduced, namely a consolidation analysis and the calculation of a safety factor by means of a safety analysis (phi/c-reduction). It also involves the modelling of drains to speed up the consolidation process.

The attached *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 04: Construction of a road embankment appeared first on Plaxis.

In this lesson a suction pile in an off-shore foundation will be considered. A suction pile is a hollow steel pile with a large diameter and a closed top, which is installed in the seabed by pumping water from the inside. The resulting pressure difference between the outside and the inside is the driving force behind this installation.
In this exercise, the length of the suction pile is 10 m and the diameter is 4.5 m. An anchor line is attached on the side of the pile, 7 m from the top. To avoid local failure of the pile, the thickness of the tube where the anchor line acts on the pile is increased. The soil consists of silty sand. To model undrained behaviour, an undrained stress analysis with undrained strength parameters will be performed.

This exercise will investigate the displacement of the suction pile under working load. Four different angles of the working load will be considered. The installation process itself will not be modelled.

The attached (zipped) *.p3dlog file contains all the commands to generate the models up to calculation (without point for curves selection). With a PLAXIS VIP licence you can use the commands runner to open the *.p3dlog file and to execute all commands in one go. Without a VIP licence, you can open the *.p3dlog file with any text editor, like Notepad, and then execute the commands via the command line command by command.

The post PLAXIS 3D Tutorial 03: Loading of a suction pile appeared first on Plaxis.