Applying a circular load. Immediate and consolidation settlement. Deformed contours. Query points and query lines. Graph query.

Transcription

1 Quick Start Tutorial 1-1 Quick Start Tutorial This quick start tutorial will cover some of the basic features of Settle3D. A circular load is applied to a single soil layer and settlements are examined. The finished product of this tutorial can be found in the file Tutorial 01 Quick Start.s3z in the Examples > Tutorials folder in the Settle3D installation folder. Topics covered Applying a circular load Immediate and consolidation settlement Deformed contours Query points and query lines Graph query Info Viewer Drawing tools

2 Quick Start Tutorial 1-2 Introduction Before we start the tutorial, you should be familiar with the following general information about Settle3D. Program Assumptions There are several important assumptions and limitations that must be considered when using Settle3D: Settle3D calculates three-dimensional stresses due to surface loads. However, displacements (settlement) and pore pressures are computed in one-dimension, assuming only vertical displacements can occur. This is in keeping with general geotechnical engineering practice and material parameters are specified to reflect the one-dimensional nature of the analysis. In the Horizontal Soil Layers mode, all soil layers are assumed to be horizontal and continuous. It is not possible to specify nonhorizontal soil geometry. In the Multiple Boreholes mode, nonhorizontal soil strata can be defined, but the ground surface is assumed to be horizontal. By default, applied loads are flexible, so that the stress at the surface directly below the load is constant, but the displacement is not. Rigid loading can also be specified, but is more limited in application (e.g. cannot be used with time-dependent consolidation). The ground surface is at depth = 0, depth is positive downwards, and compressive stress is positive. Program Interface In order to carry out the various modeling and interpretation tasks, Settle3D provides two distinct views: The Plan View is a top-down view of the ground surface and is used to define load geometries, queries, drawing tools etc. The 3D View enables easy visualization of results in three dimensions. In addition, the Sidebar at the right of the screen provides a variety of viewing controls and the contour legend. In general, both views and the sidebar are visible, but their relative sizes can be scaled as desired.

3 Quick Start Tutorial 1-3 Defining the Model If you have not already done so, run Settle3D by double-clicking on the Settle3D icon in your installation folder. Or from the Start menu, select Programs Rocscience Settle3D 3.0 Settle3D. Note that when the Settle3D program is started, a new blank document is already opened, allowing you to begin creating a model immediately. Project Settings The Project Settings dialog allows you to enter project information, set the unit system and specify other general analysis parameters. Open the Project Settings dialog from the toolbar or the Analysis menu and make sure the General tab is selected. Set the Stress units = Metric, stress as kpa and the Settlement units = millimeters. Click on the Project Summary tab and enter Quick Start Tutorial as the project title. Click OK to save your input and exit the dialog.

4 Quick Start Tutorial 1-4 Adding a Load From the Loads menu, choose Add Circular Load. Alternatively you can click the circular load icon in the toolbar as shown on the left. For the rest of the tutorial, equivalent toolbar icons will be shown in the margin beside the relevant text. In the Define Load dialog, change the circle radius to 7 m. We will use the default load magnitude of 10 kpa, Load Type = Flexible and depth = 0 (i.e. load is placed on the ground surface). Click OK to close the dialog. You will now see a circle that needs to be placed somewhere on the Plan View. You can click the mouse to place the circular load, or alternatively you can enter the coordinates in the prompt line at the bottom right of the screen.

5 Quick Start Tutorial 1-5 Enter 5,5 and hit Enter to place the centre of the circular load at the coordinates 5,5 in the Plan View. You should now see the circular load in both the Plan View (left) and 3D View (right). You can zoom to the extent of boundaries by selecting the Zoom All toolbar button or pressing the F2 function key. Your model should now look like this. Soil Layers The 3D view shows a soil layer with a default thickness of 20 meters. It is assumed that rigid bedrock lies below the soil. In this section we will learn how to change the soil properties and layer geometry. Soil Properties Select Soil Properties from the toolbar or the Soils menu, and enter the following properties under the first tab of the dialog. Change the name of the soil to Medium Clay. Leave the default Unit Weight of 18 kn/m 3. You can use the checkboxes to enable or disable the input for Immediate Settlement, Primary Consolidation or Secondary Consolidation. If a checkbox is selected, then the corresponding settlement type will be computed for that material. By default only the Primary Consolidation checkbox is selected.

6 Quick Start Tutorial 1-6 Select the Immediate Settlement checkbox. The parameters for immediate settlement determine the instantaneous settlement before consolidation starts. These are essentially undrained material properties. The parameter Es is the one-dimensional Young s modulus commonly used in settlement analyses. Leave the default values for Es and Esur. See the Settle3D help for detailed information about the input parameters. The Primary Consolidation parameters determine the settlement that occurs as pore pressure dissipates and the soil compacts over time. In this tutorial, we are not looking at time-dependent consolidation so these parameters will only influence the longterm settlement after all excess pore pressure has dissipated (sometimes called ultimate settlement). Change the Material Type to Linear. For a linear material we only need to specify mv, which is the one-dimensional compressibility. We will use the default parameter values (mv =0.0002). For most of the material input 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 estimates of parameter values if you do not have your own analysis data. This is left as an optional exercise, after completing this tutorial.

7 Quick Start Tutorial 1-7 We are only defining a one material model, so select OK to save the selections in the Soil Properties dialog. Layer Thickness To define the thickness and sequence of the soil layers select Soil Layers from the toolbar or Soils menu. Here you can add layers of different material and change their thickness. We will specify only one layer of material but we will change the thickness to 25 m. The dialog should look like this. Click OK to close the dialog.

8 Quick Start Tutorial 1-8 Field Point Grid Stresses and displacements are calculated on one-dimensional strings of points descending vertically from the ground surface. To compute results in 3D, an array of these 1D strings are required. The simplest approach is to automatically generate an array of strings by choosing Auto Field Point Grid from the Grid menu. You will first see the Grid Properties dialog, select OK to accept the default values. A grid will be automatically generated and stress and settlement will be automatically computed throughout the 3-dimensional volume. By default, contours of Total Settlement will be shown. Your model should now look like this. TIP: if you wish to view the location of the field points, go to View Query Display Options and under the Field Point Grid tab, choose a symbol other than None.

9 Quick Start Tutorial 1-9 View Options Before we proceed to examine the results, we will mention some useful shortcuts for zooming, panning, rotating and maximizing the views. Maximize Plan View or 3D View Within the Plan/3D View, you can quickly maximize the Plan View or the 3D View by double-clicking in the desired view. To restore the split-screen presentation, double-click again in the maximized view. You can also select the toolbar shortcut buttons Expand Plan View, Expand 3D View, Split Plan/3D View - to maximize the Plan View, the 3D View, or restore the split-screen format. Mouse wheel zoom You can easily zoom in or out by rotating the mouse wheel forward or backward. Mouse wheel pan You can quickly pan the views by holding down the mouse wheel and dragging the mouse. Rotate 3D View You can rotate the 3D View by holding down the left mouse button and dragging the mouse in the 3D View. Reset View If you want to reset the default viewing angle of the model in the 3D View, right-click in the view and select Reset View from the popup menu. A variety of other viewing and display options are available through the right-click menu, the sidebar and other shortcuts, these can be explored after completing this tutorial.

10 Quick Start Tutorial 1-10 Results Visualization Total Settlement You should be looking at contours of total settlement in the Plan view and 3D View. Under the Contour Legend in the Sidebar you can see that the maximum settlement is 33.2 mm. You can visualize this displacement in the 3D view by selecting the Deformed Contours checkbox in the View Controls in the Sidebar. If you rotate the 3D view (hold down the left mouse button and move the mouse), then you should see a screen like this: TIP: the deformation of the surface is multiplied by a default scale factor. To change the scaling of this deformation, go to View > Query Display Options > Field Point Grid > 3D View and change the deformation Factor. By default, the settlement at the ground surface (Depth = 0) is shown. You can examine the settlement at different depths by using the depth control in the Sidebar. The Settlement at a depth of 5 m looks like this:

11 Quick Start Tutorial 1-11 TIP: you can change the contour range, interval and color scheme by choosing Contour Options from the toolbar, View menu or right-click menu. Turn off the deformed contour display, and reset the depth control to zero. Plotting Other Data Types In the toolbar at the top of the screen, you can change the data type being plotted. As well as Total Settlement you can select Immediate Settlement or Consolidation Settlement. For this example, the Total Settlement is the sum of the Immediate Settlement and Consolidation (long-term or ultimate) Settlement. Therefore plotting either one of these will show less displacement than the Total Settlement. In this case, the maximum immediate settlement is 11.1 mm and the maximum consolidation settlement is 22.1 mm. As you can see from the contours, these values occur at the center of the flexible circular load. You can also plot the Loading Stress or Total Stress. The Loading stress is simply the stress due to the load, whereas the Total Stress is the Loading Stress plus the stress due to gravity (i.e. self-weight of the soil).

12 Quick Start Tutorial 1-12 Queries To obtain results at specific locations, you can add Query Points or Query Lines. These allow you to graphically plot data versus depth or horizontal distance, at any location in the model. Query Points From the toolbar or the Query menu, select Add Query Point. You will see the Query Point dialog as shown. A Query Point is actually a vertical line that divides the soil layer(s) into sub-layers (divisions). Stress and displacement are calculated for each sub-layer. More divisions generally produce more accurate results. This dialog allows you to specify the number of divisions for each layer. Leave the default choice of Automatic. This will generate subdivisions such that the discretization is denser near the ground surface where the high stress gradients are likely to be. Click OK and the cursor will become a cross-hair in the Plan View. You now need to specify the location of the Query Point on the surface. You can click the mouse at the desired location or you can manually enter coordinates in the prompt line at the bottom right of the screen. Enter the coordinates 5 5 to place the Query Point at the centre of the circular load. If you are still viewing Total Settlement, your screen should now look like this.

13 Quick Start Tutorial 1-13 In the 3D View you can see the Total Settlement plotted along the vertical line represented by the query point. To graph the query data select Graph Query from the Query menu. Select the Query Point using the mouse and hit Enter. You will see the following dialog: Choose Total Settlement if it is not already selected and hit OK. You should now see a graph that looks like this:

14 Quick Start Tutorial 1-14 As expected the amount of settlement decreases with depth. At the bottom of the soil layer, the settlement is zero because the soil is assumed to be underlain by rigid bedrock. You can now easily plot other data by selecting from the list in the toolbar. Query Lines Toggle back to the model view by clicking the Plan / 3D View tab at the bottom left of the screen. From the Query menu select Add Query Line. You are first prompted for the number of horizontal divisions. Leave the default value of 20. As with a Query Point, you are also prompted for the number of vertical divisions. This time select Evenly Spaced Divisions and change the number to 25. This will generate 20 vertical strings with 25 divisions in each string. Click OK and you will now be prompted for the start point of the line. With the mouse, select the existing query point at the centre of the circle. You will now be prompted to enter the second point. Using the keyboard, enter the coordinates 5-9. Hit Enter.

15 Quick Start Tutorial 1-15 The Query line will appear on the Plan View with bars giving the Total Settlement along the line. The minimum and maximum values are shown numerically. The 3D View will show a vertical cross-section with contours of Total Settlement. To see this more clearly, turn off the Point Query display (clear the checkbox next to Point Queries in the Sidebar under View Controls), and rotate the model in the 3D View until the screen looks as follows: You can plot the data by selecting Query Graph Query and selecting the query line (or by right-clicking on the line and choosing Graph Query). Choose the data you wish to plot (Total Settlement) and click OK. You will see a graph showing the Total Settlement versus horizontal distance along the line, at the current depth. This is the Total Settlement along a line at the ground surface.

16 Quick Start Tutorial 1-16 You can change the depth of the line by using the depth control in the Sidebar of the Plan View. You can also change the data being plotted using the drop-list in the toolbar. Close any extra windows so that only the Plan View window and query line chart windows are open. Tile the windows so that they look like the window below. Click on the Plan View window, and the depth control sidebar will appear. Change the depth to 5m. Both the Plan View and Chart View results will change to those at 5m. Click on the Chart View and change the dropdown results type to Loading Stress. Click on the Plan View window and do the same. You are now looking at the contour and query line results for Loading Stress at a depth of 5m. The window should look like the figure below. TIP: you can export this data to a Microsoft Excel spreadsheet by simply right-clicking on the graph and choosing Chart in Excel. If you prefer another spreadsheet program, then choose Copy Data to Clipboard and you will be able to paste it into any Windows program.

17 Quick Start Tutorial 1-17 Info Viewer The Info Viewer presents a formatted summary of input data and analysis results. Select the Info Viewer option from the toolbar or the View menu. The Info Viewer Controls in the sidebar allow you to customize the information which is displayed in the Info Viewer, and the appearance of the information (e.g. fonts, colours, etc). The Info Viewer information can be exported in a variety of ways. If you right-click in the Info Viewer, you can copy, view in browser, or save the information to a file. You can also print the Info Viewer, and customize the print output using the Page Setup option in the File menu. This is left as an optional exercise.

18 Quick Start Tutorial 1-18 Drawing Tools As a final exercise, we will mention the Drawing Tools which allow you to add a variety of drawing objects to the Plan View. For example, you can add a table of soil properties as follows: 1. Switch back to the Plan/3D View, and select the Soil Properties Table option from the toolbar. 2. Click the mouse in the Plan View to add the table, as shown in the figure below. 3. After adding the table, it can be edited, moved or formatted (e.g. double-click on the table to display the Format Tool dialog). See the help for more information. This concludes the Quick Start Tutorial; you may now exit the Settle3D program.