Import Slide2 Model

1. Introduction

The simplest type of 3D slope model is a 2-dimensional slope profile which has been extruded in the third dimension to create a 3D slope with a constant profile.

In this tutorial, we will demonstrate the Slide Import option, which allows you to import 2- dimensional slope models from the Slide program, into Slide3 as 3D extruded slope models.

This feature is useful for comparing 2D slope stability results with equivalent 3-dimensional models, to evaluate the significance of 2D versus 3D modelling. In general, 3D extruded slope models tend to give higher safety factors than the 2D counterparts, due to the “end effects” of the 3D surface. However this may not always be the case, and results can vary depending on the model.

2. Slide (2D) Model Files

It is assumed that you are familiar with the Slide program and have access to it. However, if that is not the case, the Slide example files are included with your Slide3 installation so that you can try out the Slide Import option.

For convenience, many of the Slide (2D) tutorial and example files have been installed with your Slide3 installation. The quickest way to access these files is to use the menu shortcut:

File > Recent > Examples > Slide2 Example Files

In the Open file dialog, change the file type to Slide Files:

You can also open Slide2 files using the options described below.

Import Slide Files

There are two (equivalent) ways to import a Slide2 file into Slide3:

1. Select File > Import > Import Slide Project and navigate to the folder Slide2 Example Files to open Tutorial 04 Composite Surfaces.

2. Select File > Open Project and select Slide Files as the File Type, and within the Slide2 Example Files folder, open Tutorial 04 Composite Surfaces.

If you already use the Slide2 program, then you can of course access your own Slide2 folders to import files from. If you do not have the Slide program installed, then the Slide2 tutorial files can be found in your Slide3 installation folder, in the Slide2D Tutorials sub-folder at the following path:

C:\Users\Public\Documents\Rocscience\Slide3 Examples\Tutorials\Slide2D Tutorial Files

3. Slide (2D) Tutorial 4: Composite Surfaces

Import the file Slide2 Composite Surfaces. Select Group1, Scenario1 (Master Scenario). Select OK in the Slide2D multi-scenario selection dialogue.

After Selecting OK, Import Slide Project prompt will show up. Press OK with extrusion depth of 230m (set by default).

You should see the following 3D model. It is a “weak layer” model which is assumed to have strong bedrock below the weak layer. The model also has a water table and a distributed load at the top of the slope.

Symmetry

When you import Slide2 models into Slide3, the Symmetry option in Project Settings is automatically turned on, and the location of the line of symmetry is automatically calculated based on the extruded length of the model.

Select: Analysis > Project Settings > Symmetry

Select Cancel in Project Settings.

Slip Surface Options

Select: Surfaces > Slip Surface Options

Notice that the checkbox for External Geometry Composite Surfaces is selected. This option considers all slip surfaces which intersect the lower edge of the External volume, to travel along the External boundary.

Notice that the Surface Type = Spline and the Search Method = Particle Swarm Search. Select OK.

If you run Compute you should see the following results.

4. Compute

Save the model.

From the drop down menu, under Analysis, select "Compute", or Compute icon

5. Results

Select the Results workflow tab

Select Show Contours icon .

You should see the following:

6. Search Options

Select: Surfaces > Slip Surface Options

Turn on the Surface Altering Optimization checkbox. Select OK.

Save and select Compute to re-run the analysis.

7. Results

Select the Results workflow tab

With Surface Altering Optimization, you should see the following results. The safety factor has been lowered with surface altering optimization. This highlights the importance of search methods. In general, the Surface Altering optimization search option should be turned ON for most models.

Compare the 3D and 2D results by running the model in Slide2.

Try opening and running other Slide2 models in Slide3, and compare the 2D and 3D surfaces and safety factors, with and without surface altering optimization.

8. Additional Exercises: Slope with Tieback Support

Open the Slide2 file Tutorial 06 Support (choose the scenario – With Tieback Support).

Compute the results and compare