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Soil Properties
Material properties in Settle3D are defined in the Soil Properties dialog shown below. Up to 20 different soil types can be defined for a single model. The following material property options are available:
A summary of the input parameters is given below. For detailed information about the definitions of Settle3D material parameters, see the Settle3D Theory Manual.
Soil Properties dialog
After defining the soil properties, the sequence and thickness of soil layers is defined in the Soil Layers dialog.
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Soil Properties: Immediate Settlement
Immediate settlement parameters consist of:
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1-dimensional Young's modulus: Es
1-dimensional unload/reload modulus: Esur
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If you do not want to consider immediate settlement in the analysis, you can turn off the Immediate Settlement checkbox for any material. If the checkbox is turned off, immediate settlement will not be computed for that material, and will be set to zero for the analysis.
Immediate settlement material parameters
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Soil Properties: Primary Consolidation
Primary consolidation parameters can be defined in terms of four different models:
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Linear
Non-Linear
Janbu
Koppejan
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If you are modeling time-dependent consolidation, then you will also be able to enter time-dependent consolidation parameters, as illustrated below. (If you are not considering time-dependent consolidation, then these parameters will be disabled).
Primary consolidation parameters (non-linear)
Primary consolidation parameters (linear)
Primary consolidation parameters (Janbu)
Primary consolidation parameters (Koppejan)
For further information see the Settle3D Theory Manual.
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Soil Properties: Secondary Consolidation
Secondary consolidation (i.e. creep) parameters can be defined using either standard or Mesri models. For the standard model the parameters are:
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Secondary compression index: Ca
Secondary recompression index: Car
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Secondary consolidation material parameters
Secondary consolidation material parameters (Mesri)
If you do not want to consider secondary consolidation in the analysis, you can turn off the Secondary Consolidation checkbox for any material. If the checkbox is turned off, secondary consolidation will not be computed for that material, and will be set to zero for the analysis.
For further information see the Settle3D Theory Manual.
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Soil Properties: Property Assist Dialogs
For most of the material parameters in the Soil Properties dialog, you will notice a Pick
 icon beside the input edit box. If you select this button, you will see a dialog with published test results for a variety of soil types. This allows you to obtain reasonable estimates of parameter values, if you do not have your own analysis data.
Permeability data for various soil types
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Soil Properties: Vary by Depth
If you wish to define material properties which vary linearly with depth, select the Properties vary by depth checkbox, at the bottom of the Soil Properties dialog.
If this checkbox is selected, you will be able to enter a Top and Bottom value for most parameters (i.e. the value of the parameter at the top of a soil layer and the bottom of a soil layer). The top and bottom values are indicated by the letters t and b beside the applicable edit boxes, as shown in the figure below. A linear variation is assumed between the top and bottom values. If a given parameter does NOT vary by depth, then simply enter the same value for the top and bottom.
Soil properties dialog (properties vary by depth)
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Soil Properties: Strain Based
For the non-linear consolidation model, you can choose the Strain based Cc, Cr, and Ca option, at the bottom of the Soil Properties dialog.
In this case the Primary and Secondary Consolidation input parameters will request strain based compression and re-compression index values.
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Soil Properties: Wick Drains
If your model includes wick drains, you can customize the horizontal flow properties for each material, by selecting the Wick Drains button in the Soil Properties dialog. You will see the following dialog, which allows you to specify the ratio of horizontal to vertical flow in terms of either consolidation or permeability coefficients.
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Soil Properties: Layer Modulus
If you are using the Multiple Layer stress computation method, you can define the elastic modulus of each soil layer by selecting the Layer Modulus button in the Soil Properties dialog and choosing one of the following options.
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Soil Properties: Hydroconsolidation
Certain soils (e.g. loose clayey sand), when exposed to water, experience a significant volume reduction. This is referred to as hydroconsolidation or soil collapse. The amount of collapse depends on the stress. At very low stresses, these soils may actually exhibit swelling.
Hydroconsolidation properties are defined in the following dialog, which allows you to define a hydroconsolidation curve in terms of either stress versus strain or stress versus void ratio.
Hydroconsolidation properties dialog
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Soil Properties: Editing
Soil properties and soil layers can be easily edited, allowing you to quickly carry out parametric analysis. For example, if you right-click on a soil layer in the 3D view, you can quickly access the Soil Properties or Soil Layers dialog from the popup menu. This will take you directly to the properties of the layer on which you clicked.
Right click editing shortcut in 3D view
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