This lesson describes the construction of an excavation pit in soft clay and sand layers. The pit is a relatively small excavation of 12 by 20 m, excavated to a depth of 6.5 m below the surface. Struts, walings and ground anchors are used to prevent the pit to collapse. After the full excavation, an additional surface load is added on one side of the pit.

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 02: Excavation in sand appeared first on Plaxis.

In this chapter a first application of PLAXIS 3D is considered, namely the settlement of a foundation in clay. This is the first step in becoming familiar with the practical use of the program.
The general procedures for the creation of a geometry, 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 chapter will be utilised in the following lessons. Therefore, it is important to complete this first lesson before attempting any further tutorial examples.

The attached (zipped) *.p3dlog files contain 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 01: Foundation in overconsolidated clay appeared first on Plaxis.

Versions: PLAXIS 2D 2017, PLAXIS 3D 2017

Description

With the released versions of PLAXIS 2D 2017 and 3D 2017, an improvement was made in structuring the properties for Phase and Step objects in PLAXIS Output program.

Below you will find more details regarding the changes in the objects in Output and how to view the value for the new objects using the command line.

Phase and Step object changes

The Phase and Step objects have the same properties in Output program. For simplicity, in this article, we will only write about the Phase object.

The main change in the Phase object concerns the rearranging of the properties to fit a better object structure related to the type of value provided:  two new child-objects are created with the following names:

• InputSettings
• Reached

These two new objects can be easily inspected by using the echo command for a specific phase, e.g. echo Phase_6

InputSettings

The InputSettings object contains all the information regarding the settings defined in Input program. For instance, this includes the following settings:

• TimeInterval
• IgnoreUndrainedBehaviour
• UseUpdatedMesh

For more information, you can run the following command in the command line, e.g.: echo Phase_6.InputSettings

Reached

The Reached object contains all the calculation information for a phase including the following:

• SumMsf
• SumMstage
• RelativeStiffness

For more information, you can run the following command in the command line, e.g.: echo Phase_6.Reached

Command line changes

The changes in the Phase and Step object affects the commands used to retrieve any of the values that belong to these objects.

Below you can find some examples on how to retrieve the values in 2D 2017 and PLAXIS 3D 2017 using the command line in comparison to the old command with previous versions:

• OLD command: echo Phase_6.Info.UseCavitationCutOff
• NEW command: echo Phase_6.InputSettings.UseCavitationCutOff
  

• OLD command: echo Phase_6.Info.DeformCalcType
• NEW command: echo Phase_6.InputSettings.DeformCalcType
  

• OLD command: echo Phase_6.Info.UseUpdatedMesh
• NEW command: echo Phase_6.InputSettings.UseUpdatedMesh
  

• OLD command: echo Phase_6.Info.SumMstage
• NEW command: echo Phase_6.Reached.SumMstage
  

• OLD command: echo Phase_6.Info.ForceY
• NEW command: echo Phase_6.Reached.ForceY
  

• OLD command: echo Phase_6.Info.RelativeStiffness
• NEW command: echo Phase_6.Reached.RelativeStiffness

The post PLAXIS Output Phase/Step object compatibility appeared first on Plaxis.

For now, we strongly advise not to check the Ignore suction option for a fully coupled flow-deformation analysis in PLAXIS 2D and PLAXIS 3D to allow for full development of suction in the unsaturated zone.
In the upcoming versions, the option to Ignore suction will be disabled when selecting the Fully coupled flow-deformation analysis.

Practical usage
A fully coupled flow-deformation analysis will always take into account suction as suction is an indissoluble part of the coupling between deformation, pore pressure and groundwater flow.
If a project uses both fully coupled flow-deformation analysis phases as well as other types of calculation phases, it is technically possible to ignore suction in the other types of calculation phases, however, we recommend not to do so. Changing from a situation with suction to a situation without suction is physically not realistic and numerically creates an unbalance that has to be solved which then may lead to unrealistic additional deformations, excess pore pressures or stresses. When using fully coupled flow-deformation analysis as part of a project, best practice is to have all calculation phases take into account suction.

However, if for some reason the calculation must change from suction to no suction or vice versa, this change should be done by inserting a so-called plastic nil phase in between the phases where the change of suction is desired. In the plastic nil phase then only suction is respectively introduced or eliminated and the resulting unbalance is solved.

Safety phase
The most common reason to mix phases with different settings for suction is when having a Safety phase without suction following some calculation including suction. Taking into account suction in a Safety phase generally gives a higher factor of safety, hence ignoring suction in a Safety phase is more conservative. Because this is such a common situation Plaxis has automatically build in the Safety analysis that any unbalance due to changing from suctions to no suction is first solved before the factor of safety is determined. This means that in case of a Safety calculation the plastic nil step is not necessary: it is already part of the Safety analysis.

The post Ignore suction in Fully coupled flow-deformation analysis appeared first on Plaxis.

Thermosyphon systems are passive refrigeration devices, helping to protect the permafrost to support buildings, pipelines, railroad embankments and highways (Wagner (2014)). They are charged with a working fluid circulating between an evaporator and a condenser/radiator due to the natural convection. A schema operation example of a thermosyphon system is in Figure 1.1. In the winter, the ground temperature is higher than the air temperature, so the fluid at the base of the thermosyphon warms up, vaporises and moves upward to the radiator where the liquid cools down by colder air, condenses and moves downward again. This loop transfers heat from the ground to the air as long as the appropriate temperature difference prevails; otherwise, the system stops working. Therefore, the cycle ceases in the summer, and the cold is stored in the ground.

Figure 1.1 Thermosyphon operation (after Wagner (2014))

Conclusions

This report illustrates the thermal analysis of thermosyphon-ground systems in Geotechnical engineering using PLAXIS 2D finite element software. A typical
engineering application of thermosyphon foundation subjected to yearly air temperature variation and a permanent heated building is presented. A theoretical background of thermosyphon is briefly introduced. The key factors influencing the ground response are performance characteristics (thermal conductance) of thermosyphon, air temperature, soil thermal properties and evaporator pipe size. All these factors can be modelled by different flexible functionalities in PLAXIS, including time-dependent temperature and heat transfer functions and especially Thermosyphon boundary condition. The obtained results are consistent with physically-expected ground responses, showing the permafrost protection by a thermosyphon system.

The post Modelling of Thermosyphons Foundation System appeared first on Plaxis.

Improved features and fixed issues PLAXIS 2D 2017.01

A large number of issues have been addressed, including:

• the trim/extend options for generated tunnels
• an uncommon crash when going to mesh mode
• an issue with using imported geometry from AutoCAD in the
  tunnel designer
• a crash regarding caching when recalculating phases
• preventing a crash when loading a corrupt project
• various issues regarding the tunnel connections
• prevent ignore-suction from being selected for fully-coupled flow-stress analysis calculations
• any part of a structure can now be used with the structureplot command in Output

New and improved features PLAXIS 2D 2017.00

• all applications are 64-bit only for better performance and ability to handle larger projects
• massively improved performance and memory use, particularly when dealing with huge projects
• possibility to get a separate, floating command line window
• embedded beams support grout anchor behavior
• a Python distribution is included for easier use of the remote scripting facilities
• saving of inverse analysis settings in SoilTest
• 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
• multiselect-on-click behavior for selecting overlapping objects of the same type
• added multiply command for features and numeric properties
• possibility to apply design approaches to Hoek-Brown soil models
• possibility to automatically attach node-to-node anchor to embedded beam
• define cross and parallel permeabilities in interface material
• support for encrypting the communications between a PLAXIS application and the scripting facilities
• model explorer groups clusters based on material assignment in Output
• added more copy options for the command line session editor
• added PyQtGraph package to the Python distribution
• added Robertson type of CPT data interpretation

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 2D 2017 is 6.40. Plaxis recommends to always use the latest versions.

The post PLAXIS 2D 2017.01 appeared first on Plaxis.

The problem is already fixed for PLAXIS 2D 2017.01

When using PLAXIS 2D 2017.00 this workaround can be followed:

1. Delete all Safety phases
2. Execute the following command in staged construction mode:

   tabulate Phases "Number"

3. Count the number of phases being omitted by comparing them with the value for the .Number property
4. Add an equal number of dummy phases to the number corresponding to the omitted phases starting from the Initial Phase
5. Set the dummy phases to Not calculate status
6. Re-create the Safety phases

For example, in the following project eleven (11) dummy phases should be added in order to be consistent with the number of the omitted phases:

The post [Solved] Staged construction/Flow condition settings might not be loaded correctly in 2D 2017 appeared first on Plaxis.

for PLAXIS software updates follow this link

The post PLAXIS Software updates appeared first on Plaxis.

When switching modes, the complete geometry is redrawn and the model appears properly on screen. So, if you zoom in when in Structures mode, switch to Soil mode and back to Structures mode to get the updated zoom level.

When dealing with a lot of tunnel models with these relatively small arc segments that cause the described issue, users are advised to use PLAXIS 2D 2017.00, and not 2D 2017.01 in order to have a fluent workflow.

We are working on a solution to this problem.

The post 2D 2017.01: Drawing area not updated with small tunnel arc segments appeared first on Plaxis.

With the release of PLAXIS 3D 2017, there is a possibility with the NURBS surface generation from point cloud functionality to generate surfaces based on point cloud data.

Note: Since the feature is currently still experimental, we have not done full documentation yet to use the functionality, and it is still subjected to changes and updates.

To use this new experimental point cloud functionality:

1. If the "Toggles" subdirectory does not yet exist, please create it in your PLAXIS 3D 2017 installation folder.
2. Create an extension-less toggle file called: NURBSSURFACE_EXTENDED in the "Toggles" subdirectory.
   To do so, you can e.g.
   • create a new text file;
   • and click to edit the name;
   • remove the .txt extension at the end (you might need to show known extensions);
   • and change the name to NURBSSURFACE_EXTENDED

That should enable the full point cloud import using the parameters as described as below.

Find two examples below:

Point cloud by list of points

nurbssurface (0 0 0) (10 10 0) 6 6 2 3 "c1" (5 5 5) (0 0 0) (10 0 0) (0 10 0) (10 10 0) ...

With these parameters:

• Cornerpoints of a rectangular contour (which should cover the extent of the point cloud): (0 0 0) and (10 10 0)
• Grid: 6 6
• Min degree of polynoms: 2 ( must be a positive number)
• Max degree of polynoms: 3 (must be a positive number and >= min degree)
• Continuity: "c1" (Accepted values: "c0", "c1", "c2", "c3")
• List of points

Import point cloud from file

nurbssurface ( 0 0 0 ) ( 140 140 0 ) 25 25 1 1 "c2" "C:\cloudsample.txt"

With these parameters

• Cornerpoints (0 0 0) and (140 140 0)
• Grid: 25 25
• Min degree: 1
• Max degree: 1
• Continuity: "c2"
• Filename: path + file name

The file is expected to contain the points in the following format: every point on a separate line, space between the x y z numbers, use decimal point
Example:

100.5 100.5 100.555
200.5 200.55 123.456

It seems that using 25 by 25 grid and min/max degree of 1, the command gives quite OK results for the interpolation, but you are free to experiment.
A sample file is attached below.

The finer the grid, the better the approximation of the cloud.
Changing the min and max degree higher 1 will cause an increasingly more sinuous approximation of the surface.

Figure 1. Example from sample data

Note that no points are visualized of the point cloud used to generate the surface, it is directly interpolated.
If you want to check the generated surface, it is recommended to create a list of commands creating the individual points of the cloud with the use of Excel, and run that via a copy-paste action in the Commands runner. You could also use scripting to generate the points.

Using Python to check the point cloud data

For backchecking, the attached script can be used in order to create the points themselves from the point cloud data.

1. Run the script attached script from the menu Expert -> Python -> Run script -> Open
2. Select the pointcloud txt file and press ok.
3. Wait a bit until you receive the confirmation, press ok.

Figure 2. Example pointcloud using the experimental nurbssurface command in
PLAXIS 3D 2017 and checking via the Python script. (Click to see in higher resolution)

World coordinates

In case you are working in world coordinates with your project, you will also need to initialize the Soilcontour to the correct origin of the point cloud, otherwise, it will seem as though the interpolated surface is not there:

_initializerectangular SoilContour xmin ymin xmax ymax

Since this feature is experimental it might not generate optimum geometry or lead to a successful mesh.
However, we are looking forward to assisting users who want to use this tool and hope to receive positive and negative feedback on this experimental feature, so that we can improve it in the future.

The post Import of point clouds (experimental) – 3D 2017 appeared first on Plaxis.

PLAXIS 2D 2017 has been released with several new features.
One of them is the option to connect a node-to-node anchor to an embedded beam row not only at the top, but also to any intermediate point along the embedded beam row's line. In previous versions it was only possible to connect a node-to-node anchor to an embedded beam row only at the top or the bottom of the element. See Figure 1.

Figure 1. Node-to-node anchor connected to vertical embedded beam row

The node of the anchor created at the connection point of the embedded beam row will be directly connected to the embedded beam row.
This extra functionality allows to model situations such as combi/sheet pile walls, an example is given in the following image (Figure 2).

Figure 2. Connecting node-to-node anchors to vertical continous columns (embedded beam rows)

The post Connect a node-to-node anchor with an embedded beam row halfway appeared first on Plaxis.

Versions: 3D 2016, 3D 2017, 2D 2017

Description

In this article, a simple example is provided on how to create a line cross-section by using the Remote Scripting feature in the Plaxis Output program. In addition, the matplotlib module is used to create a chart from the results of the line cross-section. This Python script retrieves the results for total displacements of soil elements.

Python solution

By using the Remote Scripting Server in the Plaxis Output program, we can create a Python script to automatically retrieve the results for a specified line cross-section. The attached script requires the user to define the following variables:

• sample_count: this is the number of intervals used for the line cross-section
• start: this is the starting point of the line cross-section
• end: this is the endpoint of the line cross-section

The Python script will then:

• gather the results for total displacements of soil using the getsingleresult command
• report an error in case the position lies outside the generated mesh
• create and display a chart with the results

Boilerplate code

In order to use the Python script, you must make sure that your Python script can communicate with the PLAXIS application. For more information on the boilerplate code please check the following article on Using PLAXIS Remote scripting with the Python wrapper.

Note that the Python script uses the g_o variable. This variable is bound to the global object of the current open Plaxis model in Output.

Modules used

The Python script requires the following modules:

• The plxscripting module to interact with PLAXIS 3D Output
• The matplotlib module to create a chart

All modules are part of the standard PLAXIS 3D 2016 installation that includes a full Python 3.4.x distribution.

Python code

sample_count = 16
start = (2.0, 4.0, 0.0)
end = (2.0, 0.0, 0.0)
# assumes that start and end contain floats


def gather_results():
    step = [(e - s) / (sample_count - 1) for e, s in zip(end, start)]
    results = []
    for i in range(sample_count):
        position = (start[0] + i * step[0],
                    start[1] + i * step[1],
                    start[2] + i * step[2])
        result_string = g_o.getsingleresult(g_o.Phases[-1],
                                            g_o.ResultTypes.Soil.Utot,
                                            position)
        # check if position lies outside the mesh
        if result_string == "not found":
            raise Exception("Used getsingleresult for point outside mesh.")

        results.append(float(result_string))
    return results

results = gather_results()


def output_results():
    pyplot.plot(range(len(results)), results, 'r')
    pyplot.grid(True)
    pyplot.show()

output_results()

Version

This script has been made for PLAXIS 3D 2016.02 using Python 3.4.x

Notes

The current Python script can be also used for making a 2D line cross-section. The 2D version of the Python script requires the following changes:

• start and end values: should use two coordinates (x, y)
• position variable in function: requires two parameters for each coordinate

Disclaimer

This Python script is made available as a service to PLAXIS users and can only be used in combination with a PLAXIS VIP license.
You use this Python script at your own responsibility and you are solely responsible for its results and the use thereof. Plaxis does not accept any responsibility nor liability for the use of this Python script nor do we provide support on its use.

The post Automatic line cross-section chart generation using Python appeared first on Plaxis.

When opening files created with older versions, please verify that the correct geogrid material behaviour is used.

When having the original file, you can use the PLAXIS 2D 2016 Viewer to check the originally used material dataset via the menu item Project > Material information, and then choose the geogrid materials. This Viewer is available here.

We are working on a solution for this.

The post Elastoplastic geogrid material datasets from 2D 2016 turn Elastic in 2D 2017 appeared first on Plaxis.

Introduction

Often, structural engineers have to deal with the behaviour of long-term behaviour of concrete structures (modelled either as plate or volume elements). In this context, the concrete mechanical behaviour is characterized by a short-term and a long-term stiffness namely E_short and E_long.

Some users believe that starting the calculation with an elastic Young’s modulus E_short and changing it to E_short once the long-term behaviour of the structural elements is sufficient. It is not! This is due to the fact that the stress relaxation is an irreversible process and should be modelled using a constitutive law accounting for energy dissipation which an elastic model does not have.

This example underneath describes a 5 m deep and 5 m wide excavation considering first a linear elastic material with short-term stiffness E_short = 30 GPa as shown in Figure 1(a), followed by a replacement with another linear elastic material using long-term stiffness E_long = 20 GPa. It can be observed that displacements are identical.

(1a) Short-term stiffness

(1b) Long-term stiffness
Figure 1: Deformed mesh

The same conclusion can be drawn when using plate elements. First, a plate element with short-term properties EA = 15E6 kN/m and EI = 312.5E3 kN.m2/m (so E = 30 GPa and thickness t = 0.5 m) is being used as shown in Figure 2(a). Then the analysis is considering the replacement of the plate property using long-term stiffness with EA = 10E6 kN/m and EI = 208.3E3 kN.m2/m (so E = 20 GPa and t = 0.5 m). Finally, it can be observed that bending moments are identical still.
When comparing the bending moments as shown in Figure 2, no stress relaxation is being observed after changing elastic stiffness properties.

(2a) Short-term stiffness

(2b) Long-term stiffness
Figure 2: Bending moments

Workaround

One possible workaround consists in modelling the structures with short-term stiffness as a combination of a solid element and a plate element, the latest one (so the plate element) being deactivated when the long-term stiffness only should be considered.

In this framework, the solid element will be given the long-term stiffness as a Young’s modulus and the plate's property must be defined such that it represents the difference between the short-term and the long-term stiffness (see figure 3).

Here the solid elements are given an elastic Young’s modulus E = 20 GPa (corresponding to long-term stiffness) and the plate with EA = 5E6 kN/m and EI = 104.1E3 kN.m2/m (so E = E_short - E_long = 10 GPa and t = 0.5 m) is being used.

Figure 3: Modelling strategy solid-plate compound

New results in terms of Deformed mesh are presented in Figure 4.
Now it can be observed that:

1. Deformed mesh after excavation with consideration of both solid and plate elements provides an identical level of deformation compared to figure 1(a) when only using solid elements in combination with short-term stiffness;
2. After deactivation of the plate, signification change of deformation is now being observed compared to figure 1(b) indicating that stress redistribution is happening due to the removal of the plate.

(4a) Short-term stiffness

(4b) Long-term stiffness
Figure 4: Deformed mesh with new modelling strategy

Conclusion

With this specific modelling technique of combining solid and plate elements, stress relaxation associated with creep mechanisms in concrete can effectively be taken into account during plate deactivation.

The post Stress relaxation due to creep in concrete structures appeared first on Plaxis.

The generation of the colour numbers for Plaxis material datasets is based on a function that combines Red, Green and Blue (RGB) colour codes into one number, using a function that involves bit-shifting of the colour numbers.

The function is:

(B shift bits left: 16) + (G shift bits left: 8) + R

In Python, the example below will set the material colour of a material called Sand to an orange colour with R, G, B = 255, 174, 61

def get_RGB_number(R, G, B):
    # get colour number from RGB using BIT LEFT SHIFT
    iB = B<<16 # left shift 16 bits for Blue
    iG = G<<8  # left shift  8 bits for Green
    iR = R     # left shift  0 bits for Red
    return iB + iG + iR


def setMaterialColourRGB(material, R, G, B):
    material.Colour = get_RGB_number(R, G, B)


soilmat = g_i.Sand
RGB = (255, 174, 61)
# change the colour of the Sand material:
setMaterialColourRGB(soilmat, *RGB)

This code was made for PLAXIS 2D 2017 and PLAXIS 3D 2017 assuming we have a soil material named Sand.
g_i refers to the  Plaxis Input global object.

Figure 1. Changing soil material colour to orange using Python

Version

The above example is made for PLAXIS 2D 2017.00 and PLAXIS 3D 2017.00 using Python 3.4.x

The post Changing the material colour using Python scripting appeared first on Plaxis.

Versions: 2D 2017.01, 3D 2017

Introduction

The PLAXIS Output program offers the possibility using the command line to configure the plot settings in order to export this plot to a file for post-processing. In this article, different options are explained providing information on the relevant options that are available.

Plot settings

To view the current settings applied to the last plot created in Output, one can use the echo Plots[-1] command:

Figure 1. Current settings of Plots[-1] (last plot created)

In the picture above you can identify different options that can be edited with the set command using the syntax below:

Show the rulers in your plot:

• set Plots[-1].DrawRulers True

Hide the axes:

• set Plots[-1].DrawAxes False

Exclude the legend of the plot:

• set Plots[-1].DrawLegend False

Figure 2. Current view of the plot in PLAXIS Output

Below are some special items in the properties of a plot object that concern every plot to be exported:

• ResultTypes
• PlotType
• LegendSettings
• MeshSettings

These will be explained in more details below.

ResultTypes

The ResultTypes contain the different results that can be visualised in the plot. This is related to the numerous options available via the menus, e.g. Deformations, Stresses, Forces, etc..

Some examples are provided below:

Set the plot result to Total horizontal displacement u_x:

• set Plots[-1].ResultType ResultTypes.Soil.Ux

Set the plot result to Incremental vertical cartesian strains: Δε_yy:

• set Plots[-1].ResultType ResultTypes.Soil.dEpsyy

Set the plot results to Active pore pressures:

• set Plots[-1].ResultType ResultTypes.Soil.PActive

Figure 3. Plot set to show the Active pore pressures

PlotType

For every plot you can also switch between the available visualisation options of the results:

Set the plot type to show the Contour lines instead of the Shadings:

• set Plots[-1].PlotType "ContourLines"

Set the plot type to show the Coloured principal directions of a plot. Note that this is relevant to some of the plots, such as the stresses and pore pressure plots:

• set Plots[-1].PlotType "PrincipalDirections"

In any case that a typo is made, the error message contains all allowed values for the command.

Figure 4. Coloured principal direction with legend shown

Figure 5. Error message displayed for assistance

LegendSettings

This allows for changing the settings of the legend that is next to the plot. For example:

Change the number of intervals of the legend to 10:

• set Plots[-1].LegendSettings.Intervals 10

Set the minimum value of the legend to -160 in project units:

• set Plots[-1].LegendSettings.MinValue -160

Figure 6. Minimum value specified for legend

MeshSettings

Various options about the current visualisation of the mesh are stored in the MeshSettings of a plot. For example:

Show the Phreatic level in the plot:

• set Plots[-1].MeshSettings.PhreaticLevel True

Show the Fixities of the model:

• set Plots[-1].MeshSettings.Fixities True

Hide the Cluster contours of the model:

• set Plots[-1].MeshSettings.ClusterContours False

Figure 7. Fixities displayed without a phreatic level representation

Export command

After setting up the plot the next step is to use the command line to export the plot to a file
The export command has the following structure:

• export ObservablePlot "full_path/to_the/file.png"  1920 1080

An example is given below:

• export Plots[-1] "C:/Plaxis/Plots/my_plot.png"  1920 1080

This command will export the lastly created plot (Plots[-1]) to the location specified within the quotation marks using the width of 1920 and height of 1080 pixels.
Note that the width and height are optional parameters which can be omitted. If those parameters are not mentioned the program will export the plot using 2880 x 2160 pixels.

Figure 8. Exported plot

Comments

• More information on Output commands and objects can be found in our Command reference under the Help menu.
• Not all plot settings are automatically applied to the current plot PLAXIS Output is showing in the plot area
• Some plot settings require the presence of another setting to be applied correctly. For instance, this is the case of showing the results using the PrincipalDirections as a PlotType. For this, the ResultType should be set to a result that includes this visualisation, as the pore pressures or stresses do, for example.
• In case of multiple plots created any changes to the plot settings will be applied to the plot specified. Plots[-1] always refer to the lastly created plot.
• A structural plot is considered a new plot and should be treated as such. In this case, Plot_1 will refer to the soil view (e.g. deformed mesh or deformations plot) and Plot_2 will refer to the structures view of the selected structural element.
  Here Plots[-1] refers to the structural plot.
• Not all commands are relevant for both PLAXIS 2D and PLAXIS 3D, e.g. ruler option is only available in PLAXIS 2D.

The post Set and export a plot in PLAXIS Output appeared first on Plaxis.

The post PLAXIS 2D Manuals appeared first on Plaxis.

The Plaxis Liquefaction Model (UBC3D-PLM) is a full 3D implementation of the UBCSAND model by P. Byrne et.al. Initially started as a User Defined Soil Model back in 2010, since the release of PLAXIS 3D 2017 and PLAXIS 2D 2018 this model is now part of the standard material library for PLAXIS VIP subscribers. More information is found in the Material Models manuals.

Model history

Update March 2018

Available as standard material model since 2D 2018.00

Update September 2017 

Available as standard material model since PLAXIS 3D 2017.00

Update January 2016 - Version of October 2016
Known issue ID: SW-10967 (Solved)

An issue with internal iterative procedures that could cause a frozen calculation process has been solved:
Inside the UBC Sand user defined soil model, there are some internal iterative procedures to deal with local (numerical) accuracy. However, in some cases, these internal iterative procedures could start diverging. Now since this is an internal procedure inside the user-defined soil model (UDSM) DLL, there will be no new communication from the UDSM to the calculation progress screen, and so the calculation gives the impression that it is frozen. In the calculation progress screen, you would see a large global error (i.e. > 1) at that moment and the calculation would not converge.

This issue with the diverging internal iterative procedures has been resolved with the version from December 2016 (v2016.0.0.0).

Update June 2013 - version 2013.150.150.0
Based on recent user feedback we improved the robustness of the model significantly.
The model description and formulation is not changed, neither the behavior of the model in a stress point (Plaxis SoilTest facility) where the strain increments are relatively small. However, the improved performance and behavior of the model can be seen in numerical models run with PLAXIS like the finite element validation example in the report (Dynamic Centrifuge, Chapter 2.3).

Note that the model is still under development and validation and a final release will be available as soon as this process comes to a final stage.

Update January 2013
A new updated version of the UBC3D-PLM model (UBCSAND 3D) implemented as a User Defined Model for Plaxis 2D and 3D. The updated formulation is in accordance with the 904aR version of the 2D UBCSAND as published recently by Beaty and Byrne (2012).
Moreover, the robustness of the model is significantly improved and more accurate results are achieved in boundary value problems. The speed of calculation in several cases where the new model is tested is dramatically improved.

The new model includes:

• An updated densification rule which is valid for stress paths which do not start from the isotropic axis. Higher accuracy achieved when anisotropic consolidation is considered.
• An updated rule for modelling the post-liquefaction behaviour in loose sands and the cyclic mobility in dense sands.
• An improved formulation which gives higher accuracy in boundary value problems and significantly improves the speed of calculation.

Note that the model is still under development and validation and a final release will be available as soon as this process comes to a final stage.

Update June 2012
Plaxis improved the PLAXIS UBCSAND-3D soil model to give higher accuracy in cyclic loading. More specifically, the new update predicts more accurately the evolution of the excess pore pressures with the use of a soil densification rule for cyclic loading and two yield surfaces for primary and secondary loading respectively. Moreover, the post liquefaction behaviour can be approximated after an extensive calibration of the input parameters with the proper element tests.
Plaxis is working on a full 3D implementation of the latest UBCSAND formulation (904aR; Beaty & Byrne, 2011). This version is expected to be released end 2012 / early 2013.

Update November 2011
Plaxis has extended the original UBCSAND model into a full 3D formulation and has made this available as a user-defined soil model (UDSM) to our users under the conditions of the PLAXIS VIP support. It is known that the version of the PLAXIS UBCSAND-3D model (October 2011) exaggerates the development of excess pore pressure upon cyclic loading, which leads to earlier liquefaction than what is observed for sands in reality. This will at least result in a conservative conclusion with respect to stability.

The post UBCSAND3D Model appeared first on Plaxis.

With the release of PLAXIS 2D 2018, a new User Defined Soil Model for liquefaction analysis is introduced, the PM4Sand model (Boulanger & Ziotopoulou, 2017).

The PM4Sand model is defined in the framework of the stress-ratio controlled, critical state compatible, bounding surface plasticity model for sand by Dafalias & Manzari (2004). The model successfully simulates material behavior of sands in dynamic loading, including the pore pressure generation, liquefaction and post-liquefaction phenomena. It is a very attractive model for the industry due to a small number of parameters to be calibrated, mostly related to the usually available data in the design practice. Note that this model has currently only been tested and validated for 2D applications.

In order to obtain the model, send your request for the PM4Sand model using this contact form. Support on the use of the PM4Sand model is only provided for this DLL under the conditions of the PLAXIS VIP support service and Article 10 of the End-User Licence Agreement.

The post UDSM – PM4Sand appeared first on Plaxis.

New and improved features PLAXIS 2D 2018.00

•  export geometry to step and dxf
• import step and dxf files
• added functionality in tunnel designer to create subsection curves from existing curve endpoints in the visualization of the
  tunnel cross-section
• added UBC3D-PLM soil model
• added preconsolidation parameters per soil layer, to allow specifying spatial variation of pre-overburden pressure
• cross-sections made in Output now respond to visibility changes done in the model explorer
• new command importcrossection to import polycurves directly into tunnels
• support for changing the selection in Input through the scripting layer
• support for unlimited number of points for curves in Output
• improved performance when making charts in Output
• added UDCAM-S material model
• added Concrete material model
• added cyclic triaxial test in SoilTest
• support for user-defined soil models in Parameter optimization
• added a 'Loads' object to structures and soil ResultType objects in Output making previous, target and current load values queryable
• loads are available for structure and soil nodes in the curve manager in Output
• improved feedback in tunnel designer for invalid geometry
• improved definition of polycurves, through additional parameters
• added FFT amplitude curve generation
• added Arias intensity curve generation and Arias duration calculation
• added extreme values display on graphs and as a separate table
• improved tabulate and filter commands, specifically for staged features, returning information on staged features in one or more phases
• support for modeling tunnel and planar contraction of plates and geogrids
• support of partial deconfinement of a tunnel
• support for dynamics calculation together with updated mesh
• support for dynamics calculation together with consolidation
• new command zoom for controlling the position and zoom level for plots in Output

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 2D 2018 is 6.40. Plaxis recommends to always use the latest versions.

The post PLAXIS 2D 2018.00 appeared first on Plaxis.