RSPile. Tutorial 3 Grouped Pile Analysis. Pile Analysis Software. Grouped Pile Analysis

Transcription

1 RSPile Pile Analysis Software Tutorial 3 Grouped Pile Analysis Grouped Pile Analysis

2 Introduction This tutorial will demonstrate how to model grouped piles under a cap. The finished product of this tutorial can be found in the Tutorial 3 Quick Start Grouped Pile Analysis.rspile2 data file. All tutorial files installed with RSPile can be accessed by selecting File > Recent Folders > Tutorials Folder from the RSPile main menu. Program Interface The RSPile modeler provides two distinct views: The Plan View is a top-down view of the ground surface. The 3D View enables easy visualization of results in three dimensions. The Sidebar at the right of the screen provides a variety of viewing controls and the contour legend. By default, both views and the sidebar are visible, but relative sizes may be scaled as desired. Model Set-Up When the RSPile program is started, a new blank document is already opened, allowing you to begin creating a model immediately. Note on sign convention: In RSPile, the default ground surface is at depth = 0, depth is positive downwards, and compressive stress is positive. Open the Project Settings dialog. This is you can change the analysis type, tolerance, number of iterations allowed, and the number of pile segments to be used in the analysis. 1-2

3 Set the Pile Analysis Type to Grouped Pile Analysis. Notice that in addition to the Axially Loaded and Laterally Loaded options, under the Individual Pile Analysis header we also have an Axially / Laterally Loaded option. We have provided the Axially / Laterally Loaded analysis type specifically for RSPile integration with Slide. The Grouped Pile Analysis setting that we re using in this tutorial is not compatible with Slide. With regards to the Analysis Settings, keep in mind that larger values of Pile Segments and Number of Iterations will increase the computation time, as calculations are performed at every node down the length of the pile. We will keep the default values for now. Click OK to close the dialog. TIP: The default units for RSPile are metric. To change this setting, select the Analysis menu and choose Units. Soil Properties Select Define Soil Properties dialog from the toolbar. In this dialog you can define the properties related to the Q-z, t-z, and p-y curves. There is a tab for each analysis type (Axial, Lateral, Driven) as well as for datum dependency. The Datum Dependency tab allows users to control linearly varying properties. For Group analyses, you can have both axial and lateral loads and for that reason both Axial and Lateral materials can be defined. We will define three layers using default properties: Clay, Sand, and a bottom Clay layer. In the Lateral tab, enter the following Lateral soil properties: Soil Property 1: Name = Top Clay Layer Unit Weight = 127 lbs/ft 3 Soil Type = Soft Clay Soil Strain Factor = 0.02 Undrained Shear Strength = 25 psf Soil Property 2: Name = Sand Layer Unit Weight = 127 lbs/ft 3 Soil Type = Sand Friction Angle = 30 Kpy = 5400 lbs/ft 3 Soil Property 3: Name = Bottom Clay Layer Unit Weight = 127 lbs/ft 3 Soil Type = Modified Stiff Clay without Free Water 1-3

4 Strain Factor = Undrained Shear Strength = 100 psf Initial Stiffness = 200,000 lbs/ft 3 Click on the Axial tab now and enter the soil properties below. The Name and Unit Weight are carried over from when we entered them previously. Soil Property 1: Soil Type = API Clay Undrained Shear Strength = 25 psf Remolded Shear Strength = 20 psf Maximum Unit Skin Friction = 1,000,000 psf Maximum Unit End Bearing Resistance = 1,000,000 psf Soil Property 2: Soil Type = API Sand Friction Angle = 30 degrees Coefficient of Lateral Earth Pressure = 1 Bearing Capacity Factor = 40 Maximum Unit Skin Friction = 1,000,000 psf Maximum Unit End Bearing Resistance = 1,000,000 psf Soil Property 3: Soil Type = API Clay Undrained Shear Strength = 25 psf Remolded Shear Strength = 20 psf Maximum Unit Skin Friction = 1,000,000 psf Maximum Unit End Bearing Resistance = 1,000,000 psf Click OK to save your input and exit the dialog. Soil Layers Select the Edit All Boreholes dialog from the toolbar. RSPile supports multiple boreholes and non-horizontal soil strata. When multiple boreholes are defined, the program will automatically interpolate between the boreholes. In this tutorial, we will model horizontal soil strata with a single borehole. The default soil column has a single layer and is located at (0, 0). To change the Location, enter coordinates for X and Y. We will keep it (0,0) here. To add another layer below the first, select Insert Layer Below. The Name column will fill in by soil property sequence. Layers are defined by thickness by default, but may be defined by top and bottom elevation. This may be changed by toggling Define Layers by Thickness. 1-4

5 Specify the following layer thicknesses: The Soil Layer Column on the right side of the dialog will update automatically as layer thicknesses are defined. Click OK to save your input and exit the dialog. Pile Properties Select the Define Pile Properties dialog from the toolbar. Select Pile 1 and enter the properties displayed in the table below. 1-5

6 Click OK to save your input and exit the dialog. Defining the Group Select Define Group from the toolbar, or go to Piles > Pile Group with Cap. We have centralized all aspects of the cap and grouped pile definition in the Cap Designer dialog. In this dialog, the user must define the pile cap geometry, pile pattern, pile connections, and loading on the cap. The Cap Designer has 6 tabs, in which users define the group in its entirety: Shape Pattern Loading Connectivity Piles Advanced Each of these tabs are described in detail in the Online Help. Shape In the Shape tab we will define a Rectangular cap, as shown below: Pattern We will now define a custom pattern of 6 piles. In the Pattern tab, do the following: Click on the and you ll see the Pattern Options appear. Note that the Pile Property is automatically set to Pile Property

7 For Pattern Type, select Custom from the dropdown, and Enter a Pile Length of 90 ft. Click on the Append Rows icon and add 6 rows. Enter the following coordinates for the piles: Pile X Y The Pattern tab should now look like this: You ll notice now that the Connectivity and Advanced tabs have * next to their names. You must go through each of these tabs before closing the dialog to ensure you have fully defined the pile and cap. Loading Go to the Loading tab. Multiple loads can be added, and we click on to add each new load. For each load, the following must be defined: Location, Type (Moment, Shear, Axial), and Value. A Load Factor Profile can also be added, though we will not explore this feature here. We will add two loads. The dialog should look like this: 1-7

8 Connectivity Moving on to the Connectivity tab, there is where the pile head to cap connection is defined. The following options are available: Pinned Fixed Restrained (Elastically Restrained) if this connection type is selected, a Rotational Spring Stiffness value must be defined. For this case we will set all connections to be Fixed. Notice that when you click on each pile to define the connection types, the pile will be highlighted in the view on the right. A Copy option exists and should be used if you want to assign the same connection type to all piles. For this example, we could set the Connection types for Pile 1 to Fixed and Fixed, then click on Copy. The following dialog would appear, where we would select all piles. 1-8

9 After setting the Connection types the dialog should appear as shown below: Advanced In the Advanced tab we define the pile lengths and orientations. At this point it is useful to switch to the 3D View. There are five dropdown options in the Advanced tab: Length and Elevation this is where the top coordinates of piles and pile lengths are defined. Each pile can have a unique depth and length. Orientation this is where the Alpha, Beta, and Theta Angles can be defined. These angles define the orientation of the pile in terms of batter and rotation. Displacement this is where Displacement Profiles can be defined and assigned to individual piles. Multipliers this is where p-y, t-z and q-z multipliers can be defined and assigned to individual piles. Group Effect Axial and Lateral coefficients, to account for the behavior of piles in closely-spaced groups, can be defined here. Coefficients can be assigned to individual piles. Axial Coefficients are entered manually. Lateral Coefficients can be entered manually, or the Automatic option can be used. In this case we will have all piles defined with the same length and top location. 1-9

10 Click on Orientation and define the following orientations. We will not edit the inputs found under the Displacement, Multipliers and Group Effect buttons. Click OK to save your input and close the dialog. Placing the Pile Group After clicking OK, you will be prompted to place the cap in the model, either by entering the (x,y) coordinates in the prompt or using the mouse. 1-10

11 Enter Location = (0,0) and pressure Enter. You will now be asked for an elevation. Enter Elevation = 10 ft. Click OK to enter the elevation and close the dialog. You should now see the following in the 2D and 3D views. 1-11

12 Results Save and Compute the file. Results Visualization After computing, the results, Displacement X by default, will appear along the pile length. Pile Results may be toggled on or off under View Controls in the sidebar. The displayed data type can be changed in the Results Dropdown. The following results are available: Axial Displacement Axial Force Displacement X Displacement Y Rotation X Rotation Y Beam Shear Force X Beam Shear Force Y Beam Moment XY Beam Moment YZ Soil Reaction Force X Soil Reaction Force Y Soil Stiffness X Soil Stiffness Y Charts Click on Graph Pile from the toolbar. Then use the selection window to select all 6 piles. The Results tab will open and the results for all 6 piles will be graphed together. As an example, some of the graphs are shown below. 1-12

13 The right-side panel houses the control options for the Charts and Markers, Legends, Axes, Colors can be customized there. In the Chart Controls you can also use checkboxes to specify which piles you want to appear in the charts. The charts are automatically updated as you check and uncheck these boxes. 1-13

14 If you uncheck the Toggle Multichart Mode option in the toolbar the Pile dropdown will become available and you ll be able to choose between the results of individual piles. By default, when you are looking at the results of individual piles the tabular results are shown at the bottom of the window. If you want to hide this results and maximum the charts view, click on the Show/Collapse Grid button on the toolbar. Below are listed other useful options for viewing and customizing results: The charts order and visible results can be set in the Edit Charts dialog, accessed by clicking on the Edit Charts button on the toolbar. The number format in the grid can be switched between Decimal and Scientific, and the number of decimal places can be specified, in the Number Format dialog, accessed by clicking on the Number Format button on the toolbar. The results show in the tabular results section can be selected in the Edit Table Columns dialog, accessed by clicking on the Edit Table Columns button on the toolbar. The Match to charts button allows you to sync the tabular results to the displayed chart results. Results can be exported to Excel by click on the Export Data to Excel button on the toolbar. By clicking on the dropdown arrow users can choose between two options, Shown Data and All Data. Info Viewer The Info Viewer presents a formatted summary of input data and analysis results. Go back to the model view and select the Info Viewer option from the toolbar. The Info Viewer contains a summary of the model input data: Project Summary Results o Cap Results o Cap Pile Results Soil Layers Soil Properties Pile Properties Cap Settings o Shape information and diagram of pile and cap setup o Pile Locations and Pile Orientations 1-14

15 The sidebar contains the Info Viewer Controls, which allow you to select what information is displayed, and customize the appearance. The data can be exported in a variety of ways: it may be manually copied, viewed in a browser, printed, or the information may be saved as a.html file. Prior to printing the file, results may be formatted to your specifications. Select the Close Window option from the Info Viewer toolbar to close the viewer and return to the model view. 1-15