Bentley Communities
Bentley Communities
  • Site
  • User
  • Site
  • Search
  • User
  • Welcome
  • Products
  • Support
  • About
  • More
  • Cancel
PLAXIS | SOILVISION
  • Product Communities
  • More
PLAXIS | SOILVISION
PLAXIS | SOILVISION Wiki Modelling soil-structure interaction: interfaces
    • Sign in
    • -PLAXIS Wiki
      • +Geotechnical SELECT Entitlements [GSE]
      • -PLAXIS
        • +Software and License - PLAXIS
        • +Documentation - PLAXIS
        • +API / Python scripting - PLAXIS
        • +Known issues - PLAXIS
        • +Models - PLAXIS
        • -Tips and Tricks
          • 3D Extrusion along a curved path
          • 3D Output: show results for shadings or contour lines
          • 64 bit User Defined Soil model
          • After a consolidation analysis I have excess pore pressures in "drained" material sets. Why?
          • Application of commands: echo
          • Application of commands: Groupfiltered and Apply
          • Application of commands: Referring to objects through their index
          • Calculation Kernel Convergence log
          • Can I import a geometry in PLAXIS 2D?
          • Can I reuse existing PLAXIS 3D geometrical objects in a new project?
          • Change temporary folder for intermediate calculation data files
          • Closing PLAXIS after your calculation is finished
          • CodeMeter network error during calculation (IPv4/v6 conflict)
          • Codemeter Network Installation
          • Codemeter USB Stick behaviour
          • Command line reference
          • Compliant base and free field boundaries: check on input signal
          • Composite liner approach in PLAXIS 2D
          • Connect a node-to-node anchor with an embedded beam row halfway
          • Considerations for modelling a thick slab as a plate
          • Consolidation: Minimum Pore Pressures and Degree of Consolidation analysis may give spurious displacements of boundary nodes
          • Conversion from 2D Version 8/9
          • Conversion of PLAXIS 2D files
          • Copy/Array command in Plaxis 2D
          • Create centerline for Structural Forces in Volumes
          • Create rock bolts accurately in PLAXIS 3D
          • Creating axial force curve for Fixed End anchors
          • Deactivated loads are still visible in PLAXIS Output
          • Definition of a bending moment as load
          • Definition of Hoek-Brown model parameters in Plaxis
          • Drained Settlement Vs. Consolidation: Differences at Failure in Output
          • Drift correction for dynamic input signal from file
          • During a calculation some plastic points disappear. How is that possible?
          • Dynamic Load with Perpendicular Distribution
          • Encrypted scripting server vulnerable to replay attacks
          • End bearing of plates
          • Energy saving while running multiple calculations
          • Error when generating 3D mesh
          • Export and format plots from PLAXIS Output
          • Export or reuse geometry for New Analysis
          • Extended command syntax for mesh generation
          • Fixed and Compliant base: what input motion is required?
          • Fixities and deformation boundary conditions
          • Force envelope results explained
          • Fundamentals of pseudo-static analysis in PLAXIS
          • General modeling guidelines - recommendations
          • Graphics card issues
          • How do I import a geometry in PLAXIS 3D?
          • How does Plaxis deal with water pressures during dynamic calculations?
          • How does Reset displacements to zero work?
          • How does the option volumetric strain work?
          • How to activate a dynamic load
          • How to change the PLAXIS model width
          • How to check undrained shear strength using Undrained A?
          • How to convert PLAXIS V21 material database to the V22 format
          • How to define and edit a material via the command line
          • How to get a load - displacement curve using SumMstage
          • How to prescribe a dynamic displacement
          • How to run a Limit Equilibrium Method analysis from PLAXIS 2D
          • How to select more than 10 nodes to be used for a curve
          • How to setup the number of steps stored in PLAXIS Input
          • How to setup tied degrees of freedom
          • How to use command log files
          • How to validate a material via the GUI and command line
          • I use PLAXIS and it says I do not have the proper entitlements
          • Improving speed of mesh generation in combination with stage generation
          • In Plaxis Curves it is possible to plot Force Fx, Fy and Fz. What are these parameters?
          • Initial degree of saturation for soil activated during staged construction
          • InputSettings object in Output
          • Inspect intermediate step results in PLAXIS Output
          • Install latest 2D version and 2D AE for converting older files
          • Is it possible to apply a distributed load on tunnel lining in PLAXIS 2D?
          • Is PLAXIS 3D 64-bit?
          • Is PLAXIS 3D enabled for multicore?
          • Iterative settings: desired minimum and maximum
          • Iterative settings: Influence of Arc length control
          • Iterative settings: Max unloading steps (arc length control)
          • Key not bound to machine
          • Language reset in PLAXIS 2D and 3D
          • Launch PLAXIS 2D calculations via DOS commands
          • Load activation in time
          • Local axis and its colour indication
          • Macros using the commands runner
          • Material datasets for plates: sheet pile wall in bending
          • Materials overview in the Model explorer
          • Memory usage in dynamic calculations
          • Mesh alignment in flow problems
          • Mesh generation might not work under Windows 7 due to security settings
          • Modelling a tapered pile
          • Modelling Rock mass using discrete discontinuities vs Jointed Rock
          • Modelling soil-structure interaction: interfaces
          • Modelling technique: Vacuum consolidation
          • Modifying boundary conditions
          • Multicore CPU and 32/64-bit
          • Node-to-Node anchors as an alternative for Fixed-End anchors
          • Non-consecutive order of step numbers in Plaxis
          • Obtain Object names easily to use in commands
          • Obtaining tabulated data from PLAXIS Input
          • On different failure criteria for soils
          • On the initialisation of the temperatures of solid elements
          • On the use of dynamic boundary conditions
          • Opening old PLAXIS project gives a popup window. What should I do?
          • Output of flow results through interfaces
          • Output project compatibility
          • Permeability in interfaces
          • Permeability in interfaces: Practical situations
          • Pile modelling in a 2D plane strain model
          • PLAXIS 2D Command compatibility notes
          • PLAXIS 3D 2013 and older PLAXIS files
          • PLAXIS 3D 2016: Fully parametric geometry
          • PLAXIS 3D Command compatibility notes
          • PLAXIS Legacy version and supported CodeMeter drivers
          • PLAXIS Output Phase/Step object compatibility
          • PLAXIS Silent Installation
          • PLAXIS Soil model numbers in command line
          • Plaxis uses SMC files for earthquakes, but what kind of format is this?
          • Points of interest for pile modelling in a 2D plane strain model
          • Problems related to non-associated plasticity
          • Program responds that drivers are out of date, but I have a newer version installed
          • Pseudo static acceleration
          • Re-use materials from other projects
          • Reduction of stiffness does not lead to a change in displacements
          • Regenerate staged construction
          • Run multiple calculations easily
          • Safety analysis and displacements
          • Safety analysis and undrained behaviour
          • Safety analysis and Updated Mesh
          • Safety calculation with a Target Value
          • Saving PLAXIS files for an older version
          • Select points for curves prior to calculation directly in Input
          • Selecting points for curves
          • Set multiple phases to be calculated
          • Showing a list of embedded beams by length
          • Smart selection of line elements in PLAXIS 2D Input
          • Stiffness units for structural elements in an axisymmetric model
          • Stress relaxation due to creep in concrete structures
          • Stresses in non-porous materials
          • Swept meshing in PLAXIS 3D
          • Tension cut-off in interfaces for User Defined Soil Models
          • Time step used in dynamic calculation
          • Trim and extend a line in PLAXIS 2D
          • Tunnels in PLAXIS 3D: Extrusions and cutting planes
          • Unable to select points for curves
          • Unable to select structures or nodes
          • Use of wells in PLAXIS 3D
          • Using an accelerogram for Dynamics
          • Using partial geometry for interesting result images in PLAXIS 3D
          • Using PLAXIS Remote scripting with the Python wrapper
          • Waterlevel inspection and editing in PLAXIS 2D
          • Westergaard's added mass for hydrodynamic pressures: a simple case
        • +Publications
        • +Videos - PLAXIS
      • +PLAXIS LE
      • +PLAXIS Monopile Designer
      • +SOILVISION
      • +Subscription Entitlement Service
    • +Working from home with PLAXIS
    • +Working from home with PLAXIS LE

     
     Questions about this article, topic, or product? Click here. 

    Modelling soil-structure interaction: interfaces

    Application PLAXIS 2D
    PLAXIS 3D
    Version PLAXIS 2D
    PLAXIS 3D
    Date created 20 August 2012
    Date modified 20 August 2012

    To simulate the interaction between a structure and soil you can apply interface elements. Without an interface the structure and the soil are tied together: no relative displacement (slipping/gapping) is possible between structure and soil.

    By using an interface, node pairs are created at the interface of structure and soil. From a node pair, one node belongs to the structure and the other node belongs to the soil. The interaction between these two nodes consists of two elastic-perfectly plastic springs. One elastic-perfectly plastic spring to model the gap displacement and one elastic-perfectly plastic spring to model slip displacement. Also see the connectivity plot of a soil-structure connection with and without interface.

    Note: for a clear display in the connectivity plot the node pairs are drawn with a certain spacing in between, where actually in the calculation kernel the two nodes have the same coordinates. The spacing between the node pairs can be influenced by the scale factor in the connectivity plot (this scale factor is then remembered in other Output plots).

    The level at which (plastic) slipping occurs is directly controlled by the strength properties and the Rinter value of the relevant material set. These parameters are by default taken from the material set of the adjacent soil cluster. Directly appointing a material set to the interface is however also possible and allows for direct control of the strength properties (and thus the interface strength) without changing the properties of the soil cluster.

    The elastic shear and normal stiffness of the interface springs are internally calculated from the stiffness properties of the relevant material set. The stiffness is chosen in such a way that the program is numerically stable and elastic deformations are negligible. Note that the relevant properties by default are also taken from the adjacent soil cluster. However, when you want to influence the stiffness of the interface, in general you should directly apply a material set to the interface. By adjusting the stiffness properties of this material set you can directly influence the stiffness of the interface without changing properties of soil clusters.

    Note the following:

    • Changing the Rinter influences both the stiffness and the strength properties of the interface;
    • When using very low values for Rinter the interface stiffness may become so low (it has a quadratic dependency on Rinter) that it results in (possibly unrealistic) gapping or overlapping between soil and structure;
    • Gapping is also possible between the structure and the soil when the tension cut-off of the relevant material data set is activated (meaning that no tension is allowed in the interface).

    Please note that a connectivity plot may be helpful in gaining insight in the way soil and structures are connected. When looking at the connectivity plot you can also select “Table” to explicitly look at the different connectivities of all interface nodes (which node is connected to which node). Also see the PLAXIS 2D/3D Reference manual for more information on interfaces.

    See also

    Numerical Analysis of Soil-Structure Interaction

    [Publications]


    On the use of dynamic boundary conditions

    [Tips and Tricks]


    Points of interest for pile modelling in a 2D plane strain model

    [Tips and Tricks]


    Permeability in interfaces

    [Tips and Tricks]


    Permeability in interfaces: Practical situations

    [Tips and Tricks]


    Using permeability in interfaces

    [Videos]

    • soil-structure
    • PLAXIS 3D
    • soil-structure interaction
    • node pairs
    • PLAXIS
    • Interface
    • PLAXIS 2D
    • Share
    • History
    • More
    • Cancel
    • Micha van der Sloot Created by Bentley Colleague Micha van der Sloot
    • When: Mon, Dec 23 2019 7:08 AM
    • Micha van der Sloot Last revision by Bentley Colleague Micha van der Sloot
    • When: Tue, Dec 24 2019 6:13 AM
    • Revisions: 2
    • Comments: 0
    Recommended
    Related
    Communities
    • Home
    • Getting Started
    • Community Central
    • Products
    • Support
    • Secure File Upload
    • Feedback
    Support and Services
    • Home
    • Product Support
    • Downloads
    • Subscription Services Portal
    Training and Learning
    • Home
    • About Bentley Institute
    • My Learning History
    • Reference Books
    Social Media
    •    LinkedIn
    •    Facebook
    •    Twitter
    •    YouTube
    •    RSS Feed
    •    Email

    © 2021 Bentley Systems, Incorporated  |  Contact Us  |  Privacy |  Terms of Use  |  Cookies