Empirical Methods

A variety of empirical methods exist for calculating immediate settlement in cohesionless soil. These methods are generally based on data from field tests (Standard Penetration Test, Cone Penetration Test, etc.) and require little user input. In general, settlement can only be calculated for regular-shaped loads (rectangles and circles). The following empirical settlement methods are available in Settle3:

• Schmertmann
• Peck, Hanson and Thornburn
• Schultze and Sherif
• D'Appolonia
• Burland and Burbidge

As currently implemented in Settle3, the empirical method options are largely independent of other modelling and analysis options in the program. This may be modified in future program upgrades, according to user feedback.

For detailed information on each method and input parameters, see the Settle3 Theory Manual.

The empirical methods can only be applied to rectangular or circular loads.

To apply an empirical settlement method:

1. Select Loads > Empirical Method and select a method from the drop down menu:
• Schmertmann
• Peck, Hanson and Thornburn
• Schultze and Sherif
• D'Appolonia
• Burland and Burbidge
2. Use the mouse to select the rectangular and/or circular loads you would like to analyze.
You cannot select any other load types (e.g. polygonal), only rectangular or circular loads.
3. When you are finished selecting, right-click and select Done Selection, or press Enter.
4. You will see a dialog corresponding to the selected empirical method. Select the Calculate checkbox at the top of the dialog. This will enable the data input for the empirical method.
5. To define the number and thickness of soil layers:
   • You can copy the existing soil profile from the Soil Layers dialog by selecting the Copy from Soil Layers button.
   • You can Export the base file, fill it with the soil profile data, and Import it back into the dialog. Exporting and then Importing ensures that the formatting of the imported file is correct.
   • Alternatively, you can use the Insert Above or Insert Below buttons to create the desired number of soil layers. In this case, the soil profile you create will be independent of the information which is entered in the Soil Layers dialog.
6. Enter the required parameters for each soil layer according to the empirical method you have chosen. See the Settle3 Theory Manual for a description of all input parameters.
7. Select OK and the empirical analysis method will be applied to the selected load(s), and the results will immediately be displayed in a textbox beside the load. The results consist of a single settlement value for each selected load.
8. You can apply any combination of (or all) empirical methods, by repeating steps 1 to 7 for each method you wish to utilize. The results of all currently applied empirical methods will be displayed in the textbox beside each load.

Right-Click Shortcut

The empirical analysis methods can also be conveniently applied or edited using the following right-click shortcut:

1. Right-click on a rectangular or circular load.
2. The popup menu will display an Empirical sub-menu, from which you may select an empirical method.
   • To apply a method, follow steps 4 to 7 described above.
   • If a particular method has already been applied to the load, a checkmark will be displayed beside the name of the method. This allows you to edit the input parameters of a currently applied method.

Turn Off Empirical

To turn off the empirical analysis:

• You can follow the steps described above, and turn off the Calculate checkbox in the empirical input dialog.
• To remove all currently applied empirical methods for a particular load, you can use the right-click shortcut described above, and select the None option.

Display of Empirical Results

To customize the display of empirical settlement results:

1. Right-click on a rectangular or circular load.
2. Select Display Properties from the popup menu.
3. Select the Empirical Results Display option and you will be able to customize the font, colour and position of the empirical results text box.