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STRUCTURAL CONCRETE SOFTWARE

Floor_Pro_Tutorial_1

111905

TUTORIAL

MODELER AND FLOOR-PRO

STRUCTURAL MODELING; FINITE ELEMNET ANALYSIS AND

DESIGN OF A SIMPLE COLUMN-SUPPORT FLOOR

Update: November 2005

Copyright 2005

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CONTENTS OVERVIEW EXERPT FROM ADAPT-MODELER MANUAL 1 – MODEL THE GEOMETRY AND BOUNDARY CONDITIONS

1.1 Geometry 1.2 Boundary Conditions

2 – APPLY LOADS 3 – SET DESIGN CRITERIA; SELECT DESIGN CODE

2.1 Design Criteria 2.2 Load Combinations

4 – ANALYZE STRUCTURE AND VIEW RESULTS 3.1 Mesh the Structural Model 3.2 Analyze the Structure 3.3 View the Analysis Results 3.4 Examine the Solution

5 – OBTAIN DESIGN VALUES AT SELECTED LOCATIONS 6 – CREATE SUPPORT LINES; LOAD PATH DESIGNATION 7 – GENERATE DESIGN SECTIONS AUTOMATICALLY 8 – DESIGN THE DESIGN SECTIONS AND VIEW RESULTS 9 – GENERATE REBAR DRAWING 10 – DESIGN FOR PUNCHING SHEAR 11 - REPORTS 12 – EXPORT DATA TO ADAPT-PT/RC APPENDIX A – DEFINITION OF ACTIONS AT A SECTION CUT

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OVERVIEW This first tutorial for the Builder platform (i) familiarizes you with the environment of the program, (ii) shows you how to generate a simple floor slab and obtain a 3D finite element solution for it, (iii) how to design the slab you analyzed, and determine the required reinforcement, and, (iv) finally, how to export data to ADAPT-PT in order to arrive at an optimum post-tensioning design for the floor system, if you intend to use post-tensioning. If you are not planning to use post-tensioning, please disregard Chapter 12, which deals with export of data to ADAPT-PT. However, if you either plan to design for post-tensioning, or wish to improve your skill in design of post-tensioned floors, it would be advisable to go through Chapter 12. The next section is an abridged description of the program environment extracted from Chapters 3 and 4 of the ADAPT-Modeler User Manual.

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EXERPT FROM ADAPT-MODELER MANUAL

3.1 ADAPT-Modeler Main Screen

Fig. 3.1-1 shows the full-screen display of the ADAPT-Modeler program, with typical features labeled for easy identification.

FIGURE 3.1-1

ADAPT-Modeler operates the same way as other Windows programs. All program tools are accessed from one of the toolbars provided by the program or through the menus provided in the menu bar at the top of the screen. Toolbars may be opened, closed, “docked” to the edge of the screen or dragged to any position on the screen as View menu item. Tools can also be accessed by clicking the right mouse button while the cursor is in the Menu Bar or Toolbar areas of the screen.

The User Information Bar displays tool-specific information and any coordinate values that may be typed by the user for specific program procedures.

The Status Bar displays such information as the mouse cursor coordinates, current unit system, snapping status, and gridline spacing and status. A short description of each specific tool also appears in this area when the mouse cursor is placed over the corresponding tool button.

3.2 Mouse Function and Operation

The primary function of the mouse is through its left-click. Depending on the mode of the program, as outlined in the next section, the left-click will result in selecting the entity below the cursor, inserting an entity or performing an operation at the location of the cursor.

Menu Bar Toolbars Docked Toolbars

Floating Toolbar

Status BarUser Information

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3.7 How to Abandon an Operation To abandon an operation you have already started, such as drawing a polygon, press the Esc key.

3.8 Main Menu

The items appearing on the Main Menu depend on the configuration of the program. The common menu items to all programs are as follows: File; Edit; View; etc.

4.3 Selection Toolbar

This toolbar contains all tools related to selecting specific elements, objects and structural components in the modelEach tool is described below.

Hint Mode. When activated, the arrow displays the identification of the entities to which it pointsIn this mode you cannot select an entity by clicking on it.

Window Selection. When this tool is highlighted, the Pick/Select mode is active. You can select an entity by clicking on it, or a group of entities by opening a window around the items while the left mouse key is held down.

Double-clicking on an entity opens its properties dialog box.

Lasso Selection. This tool allows you to draw an arbitrary polygon around a series of entities. When the lasso is closed, all entities located within or along the lasso perimeter are selected. To use this tool, do the following:

2 Click on the Lasso Selection tool.

3 Draw segments of the polygon around the entities to be selected.

4 Press C to close the lassoThe entities inside the lasso are selected automatically.

Path Selection. With this tool you can select entities by drawing a polyline through them. To use this tool, do the following:

5 Click on the Path Selection tool.

6 Draw polyline through the entities to be selected.

7 Press C to end the lineThe entities through which the line passes will be selected automatically.

Select All. This tool selects all the entities visible on the screen.

Move Selection. This tool enables you to move the entire group of entities that are currently selected. Pick a vertex of one of the entities in the selection and drag the entire group to the new location

Move Selected Point. With this tool you can move only the vertex of an entity to a new location, while the positions of the remainder of the entity’s vertices remain unchanged.

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Shape Mode Description

Selection/Pick

In this mode, you can select an entity displayed on the screen by placing the cross over it and left-clicking the mouse. Once an entity is selected, its color changes. There are two ways to enable Selection/Pick mode:

• Right-click the mouse, and select Exit

• Click on Selection/Pick Tool

Hint

In this mode, the program displays the identification of an entity that the point of the arrow touches. To change to this

mode, click on the Hint Mode Tool

Creation

In this mode, the program will create an entity, such as a line, column or slab. Place the cross at the location where you want the entity to be created and left-click the mouse. Detailed instruction for creation of each entity will be prompted on the User Information Bar at the bottom of the screen. To enable Creation Mode, left-click the mouse on the tool of the entity you intend to create. Then follow the instructions at the bottom of the screen.

Snap

In this mode, the magnet indicates that the cursor is in Snap Mode and is searching to snap onto an entity. The cursor will search for one or more entities. Once the cursor becomes close to any of the entities or conditions it is searching for, it will display a yellow sign over the location to be snapped. The shape of the yellow sign displayed identifies the entity for snapping.

Undefined Creation

In this mode, the program is requested to create an entity, although the plane on which the entity is to be created is not current. You must change the screen view (go to Plan View, if you are in Elevation) before you can create the entity in mind.

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Select the entity first. Then pick the vertex you wish to move. Drag it to the new location. The selected vertex will move independently; all other vertices will remain in their original location.

Delete Point. This tool deletes the currently selected vertex of an entity.

Insert Vertex. This tool is used to insert an additional vertex into an entity that contains multiple insertion points. The new vertex is placed between the selected vertex and the previous vertex. If the first vertex is chosen, then the new vertex is added at this end. To add a vertex, do the following:

8 Select the entity.

9 Click on the Insert Vertex tool.

10 Click on one of the entities’ vertices. Another vertex will be added to the entity, adjacent to the selected vertex.

Item’s Properties (Alt + Enter). This tool opens up the Properties dialog box for the selected entity. The properties may then be edited, as specified in other parts of this manual.

Group Selection. This tool creates a block containing all entities currently selected. The block may then be dragged as one unit across the screen.

Explode Block. This tool breaks down a previously created block into its components. It also works with blocks of imported .DWG or .DXF files.

4.4 View Toolbar

This toolbar contains tools for selecting the entities that you want to be visible on the screen, as well as for creating rendered or shaded views of the structural model.

Select/Set View Items (Fig. 4.4-1). This button is used to set the display of the project items on the screen. Depending on which boxes you select, you can display additional information about each entity. The size of the symbols representing each entity, and the font that expresses the information, is controlled by the Symbol Size and Font Size data fields. The font size for each entity can be controlled individually. If the information displayed on the screen overlaps, you can pick each text and move it around to increase the clarity of display.

The checkmarks under Display column control the view of your project in the modeling screen of the program, whereas those in the column Render refer to the 3D Viewer, controlled by the third tool described next.

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Go to Default Display. Use this button to change the items displayed on the screen to those selected in the Select/Set View Items shown in Fig. 4.4-1.

View Model. This button opens the ADAPT Solid Modeling tool (3D Viewer), where a three-dimensional, color view of the model is displayed. The view also may be captured as a bitmap and exported to other documents. An example of the 3D Viewer is shown in Fig. 4.4-2. Specific controls in the window are described in the chapter on ADAPT Viewers.

Render Design Strip. This button is used to render the Design Strips for easier viewing and verification. It toggles between showing the Design Strips with their outline or solid color.

Wire Frame. This tool sets the model view to a wire frame model.

Hidden Lines. This tool creates a model view in which hidden lines are invisible.

FIGURE 4.4-1 SELECT/SET VIEW ITEMS DIALOG WINDOW

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FIGURE 4.4-2

4.5 MODIFY/SELECTION TOOLBAR

Display All. This tool displays all the items that were visible on the screen prior to having used the Display Selection tool.

Display Selection. This tool displays on the screen only the items that you have selected.

Hide Selection. This tool hides the items you selected and displays the remainder of the items.

Create a Cut at Specified Location. With this tool you can create a display of the cross-sectional geometry of any part of your structural model. Click on the tool and follow the instructions on the screen to draw a cut across the structural model and display its geometry at the location of your choice.

4.8 SNAP TOOLBAR

This toolbar contains all the snapping tools of the program. To snap to an entity, the mouse must be in Select/Pick mode, and you must bring the cursor close to the location where you will snap the entity. Left-click the mouse to snap. The options are:

Snap to Endpoint

Snap to Midpoint

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Snap to Intersection

Snap to Intersection

Snap to Perpendicular. This tool forces the mouse cursor to snap to a target entity, such that the entity being created will be positioned perpendicular to its target.

Snap to Nearest

Snap to Grid. This tool forces the mouse cursor to snap to the nearest grid point.

Grid Settings (Fig. 4.8-1). This tool opens the Grid Settings dialog box where grid spacing, angle and other parameters can be set.

Snap Settings (Fig. 4.8-2). This tool opens the Snap Settings dialog box, where all snapping features may be selected or deselected.

Snap to Vertices of a Component. Using the previously described tools, you will not be able to snap arbitrarily to the vertices or edges of structural components, such as a beam. Since a structural component that is displayed as solid is defined by its insertion points, the insertion points will not necessarily be the vertices or edges of the entity. By clicking on the above tool, you can make the vertices and edges of all the structural components of your project capable of being snapped TO.

Note: Caution should be used when working with this tool. In order for a structural component to be correctly accounted for, in most instances it must be connected to other structural components through its insertion point. That is to say, the components must snap together at their insertion points

Create/Draw Orthogonal. This tool forces the entity being drawn or created to be positioned along either the X-axis or Y-axis.

FIGURE 4.8-1 GRID SETTINGS DIALOG WINDOW

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FIGURE 4.8-2 SNAP SETTINGS DIALOG BOX

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1 – MODEL THE GEOMETRY AND BOUNDARY CONDITIONS

1.1 Geometry You can generate a structural model in several ways: (i) you can import a DWG file and convert it to a structural model, (ii) you can use ADAPT’s drafting tools and a set of grid lines, or (iii) as we will do in this tutorial, simply draw the structure. The last option is the quickest way to become familiar with the environment and the principal features of the program.

• Open the program in either “American” or “SI” units. In this tutorial we will cover both

system of units.

In order to create a somewhat realistic structure, we will start with a grid to provide us with a sense of dimension.

• From the main toolbar click on the Grid Settings tool ( ). The following dialog window opens (Fig.1-1). Select 1ft (1m) spacing and click OK.

FIGURE 1-1 GRID SETTING DIALOG WINDOW (American/SI units)

• From the User Interface pull-down menu, select the Build Toolbar. The following (Fig. 1-2) toolbar will display. We will use this toolbar to create the geometry of our floor slab1.

FIGURE 1-2 BUILD TOOLBAR

In addition to the geometry of the structure, this toolbar enables you to specify reinforcement (base reinforcement, such as a mesh) that you want the program to account for when it

1 The plus sign “+” on the graphics of each tool indicates that the tool is for “generation” of what its graphics implies.

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calculates its reinforcement. However, for this tutorial we will limit ourselves to the first two tools: “slab” and “column.”

• Click on the Create Slab Region tool ( ). The mouse cursor changes shape to simple cross lines. Clicking the mouse, set the four corners of the slab. Use the grid as a guide to create a slab that is approximately 38x32 ft (12x10m). If the display of

the grid is too large or too small to work with, use the dynamic zoom ( ) tool to adjust the size.

o After you click on the fourth vertex of the slab, press “C” to close the slab boundary. Your slab should look similar to Fig. 1-3.

o Next click on Esc or right-click the mouse to exit the mode of creating slab regions.

o To enter the slab thickness, place the mouse on the slab boundary and double click on it. The property box of the slab (Fig. 1-4) will open. In the “Thickness” data field, enter 12 inch. (300 mm).

o Open the Location tab to view the coordinates of the slab region. If the dimensions you have created are too far from the approximate values we plan to use for this tutorial, change the dimensions by editing the data fields of the coordinates.

o Click on the check mark at the top left of the dialog box. The changes you make in the dialog box will be applied only if you click the check mark. Close the dialog box.

FIGURE 1-3 PLAN VIEW OF SLAB ON FOUR COLUMNS

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FIGURE 1-4 SLAB REGION PROPERTY WINDOW

• Click on the Create Column tool ( ) to generate the columns.

o Position the mouse at the intended location of each column, and left-click the mouse to insert a column. Each time you left-click the mouse, the program inserts one column.

o Once all four columns are in place, press Esc to exit the column insertion mode.

o Target to place the columns about 5 ft (2 m) from each side. If a column is not at the location of your choice, simply click on it. Select its center with the mouse and drag it to the location of your choice.

o If by mistake you inserted more columns than required, click on the superfluous columns and use the “delete” button on the keyboard.

o If you have too few columns, repeat the entire procedure by clicking on the Create Column tool.

o You can view the column properties created by the program by double clicking on a column to open its property box (Fig. 1-5).

o Change the cross-sectional dimensions of the Column to a reasonable value. In the figure shown, the column is assumed to be 18x18 inch (500x500 mm).

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FIGURE 1-5 COLUMN PROPERTY DIALOG BOX

Next, edit the column height. In the general case, columns are assumed to extend between the floor levels above and below the slab being designed (current plane). Each floor level is assumed to be identified by a plane. In this tutorial, we must specify the distance between the current plane (floor being analyzed) and the floor below it (bottom plane).

On Build Toolbar (Fig.1-2) click on Level Assignment ( ) tool to open the dialog box shown in Fig. 1-6. Set the distance between the current plane and the bottom plane to a reasonable value. In the figure shown, the distance between the levels is set at 10 ft (3.0 m). Click on Close.

FIGURE 1-6 DIALOG BOX SPECIFYING THE DISTANCE BETWEEN FLOORS

• Click on the “View Model”( ) tool to open the 3D viewer of the model.

• Use the different modes of display ( ) to see the model in line drawing (Fig.1-7) and other modes.

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• Rotate ( ) and zoom the model to examine its geometry. • Close the 3D viewer. The program brings you back to the main screen showing the

plan of your model.

FIGURE 1-7 THREE-DIMENSIONAL VIEW OF THE STRUCTURAL MODEL

1.2 Boundary Conditions

In this tutorial we assume that the boundary conditions the program has selected (default boundary conditions) are acceptable.

2 – APPLY LOADS

First, we define a load case. Then, we specify a load and assign it to the load case defined. The program has several pre-defined load cases. These are Dead, Live, and Prestressing. In this tutorial we will use the Dead and Live load cases of the program, and will turn the Prestressing load case off.

• From the Loading pull-down menu, select Load Case Library. The dialog window

(Fig. 2-1) shown below appears. Uncheck the Prestressing load case. Click OK to close the window.

FIGURE 2-1 LOAD CASE LIBRARY DIALOG WINDOW

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From the Loading pull-down menu select Display Loading Toolbars. The toolbar shown in Fig.2-2 will be placed on your computer screen

FIGURE 2-2 LOADING TOOLBAR

• Click on the slab edge. Change in color indicates that the slab was selected. Click on the Patch Load Wizard tool. The dialog box shown in Fig. 2-3 opens. Type 0.02 ksf (1 kN/m2) for dead load, and repeat the procedure changing the Load case to Live load and the value to 0.04 ksf (2 kN/m2). Note that the value you select for Dead load is in addition to the selfweight of the structure. The selfweight of the structure is calculated automatically by the program using the geometry of the structural model and the unit weight defined by you. The program has the commonly used unit weight value of concrete as its default value (150 pcf; 24 kN/m3)

FIGURE 2-3 DIALOG BOX FOR PATCH LOAD ENTRY

3 – SET DESIGN CRITERIA; SELECT DESIGN CODE

3.1 Design Criteria The design options—such as building codes implemented in the program, preferred reinforcing bar size, and cover to reinforcement—are all accessible through the Criteria pull-down menu. In this tutorial, however, we would assume that the default values of the program are acceptable.

Based on the default building code set in the Criteria, the program creates the appropriate load combinations. We will now add to the load combinations of the program a “Selfweight” load case. The objective is to learn how new load combinations can be created, or a pre-defined load combination can be edited.

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3.2 Load Combinations From the Loading pull-down menu select Load Combinations. The dialog window shown in Fig.3-1 opens. The dialog window shows the load cases and load combinations of the building code selected. In this case the combinations refer to ACI 2005 and IBC 2003 (displayed below the Combination list data field). Note that the load cases and load combinations show “Prestressing” and “Hyperstatic.” These are the defaults of the program. Since, in this tutorial we are not using prestressing, the program will automatically delete these from the combinations, when you enter the analysis stage. Once deleted, they will not appear in the combination. Any load, or load case for which you wish to have an independent solution to view or report, must appear on the Combination list shown on top of the dialog window. Do the following to add the Selfweight load case to the list of combinations.

• From the Load cases combo box, click on Selfweight. • Click on “Add” button to bring it to the Combination Parts window. • Using “Delete” button, remove all the other load cases that appear in the Combination

Parts. • Assign a name to the load case in the Label data field. Enter “SWGT” as the name of

this load combination. Note that the label of a load combination cannot be the same as that of a load case.

• From the Analyze/Design Options combo box, select “No Code Check.” The options of this combo box instruct the program what to do with the solution of the load case. As you will note, the options are: to perform a Serviceability, Strength, Initial, or No Code Check. In this case we intend to only view and examine the solution.

• Press OK and close the window. • Save the data.

FIGURE 3-1 LOAD COMBINATION DIALOG WINDOW

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Having defined the geometry, loading, load combinations, and accepted the other defaults of the program, such as material properties and design code, we are now ready to analyze the structure. In this tutorial, we assume that the support conditions considered by the program for the bottom of columns are acceptable. Otherwise, we could view and edit them.

4 – ANALYZE THE STRUCTURE AND VIEW RESULTS

4.1 -Mesh the Structural Model From the pull-down menu bar select FEM and click on Automatic Mesh Generation

to open the dialog box shown in Fig. 4.1-1, and accept the default values. Click OK.

(a) American units

(b) SI units

FIGURE 4.1-1 AUTOMATIC MESH GENERATION

After going through the meshing computations, the program displays the meshed slab similar to Fig. 4.1-2. Depending on the details of your structural model, it is possible that the program will interrupt, display several pink circles on your model and the message box shown in Fig. 4.1-3. Click on Continue.

FIGURE 4.1-2 PLAN VIEW OF THE SLAB MESHING

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FIGURE 4.1-3 MESSAGE BOX FOR SUGGESTED CELL SIZE We will now hide the mesh from view and continue with the analysis process.

• Click on the Select/Set View Items tool ( ). Open the tab Finite Element tab and de-select the check box Shell/Cell Element. Click the OK button to validate your selection. This should clear the display of the mesh from your screen.

• Save the data.

4.2 Analyze the Structure From the FEM pull-down menu select Analyze Structure ( ). This will perform the finite element analysis of the structure and report its completion on the computer screen. Save the data.

4.3 View the Analysis Results From the FEM pull-down menu, click on the View Analysis Results ( ) tool. This will bring up the viewer screen, as shown in Fig. 4.3-1. Next, we will view the deflection contour of the Slab.

• Click on the Load Cases/Combinations tab on the bottom left of the screen. • From the menu that opens, select Service_Combination. • Click on the Results tab at the top of the left field on of the screen. • From the list of results available select Z-Translation. This is the deflection in

the vertical direction under service loading. • Select Color Contour tool. • Click on the Display Results tool. This button turns the results on and off.

Figure 4.3-1 is the display of the viewer screen showing the contour of the deflected shape of the slab. To view a 3D-presentation of the structure’s deflected shape as shown in Fig. 4.3-2, click on the Warp Display tool.

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FIGURE 4.3-1 BUILDER VIEWER SCREEN SHOWING THE DEFLECTION CONTOUR

Use the Rotate tool to view the deflected shape in three dimensions (Fig. 4.3-2).

FIGURE 4.3-2 THREE-DIMENSIONAL VIEW OF THE DEFLECTED SHAPE An important feature of ADAPT- Floor Pro is its capability to integrate the actions over a cut (section). A cut or section is a line either drawn by you, or generated automatically by the program. The integral of the actions along a section is used for

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design and code check2. The resultant of all the forces acting over a section can be reduced to six actions – three forces and three moments. ADAPT-Floor Pro performs the summation and brings the resultant to the centroid of the cut section. Obviously, if the cut includes a beam, a step, or changes in slab thickness, the centroid will not be at the mid-plane of the slab and mid-length of the cut. For each section the centroid is calculated strictly from the geometry of the cut face. If the cut goes through an opening, or extends beyond the edge of the slab, the voids are neglected. A graphical display for the definition of the actions at a section is given in the Appendix. In the following we will create several sections to illustrate the procedure. We will target the display of the moments about Y-Y axis (vertical axis of the computer screen) for strength check.

• Click on Load Cases\Combinations at the bottom left of the screen. • Select StrengthCombination from the menu items that open. • Click on Results tab above it. • Click over the “+” to the left of the Slab Actions only. • Select Myy. A contour distribution of moment about the Y-axis should appear.

If it does not, click on the Display Results tool. • Click on the Line Contour tool.

A display similar to the diagram shown in Fig. 4.3-3, but without the cuts, will appear. Next we will examine the results by making several cuts.

4.4 Examine the Solutions Several options for display of distribution and the integral of an action at a cut are available. These are accessible through the tool buttons listed below along with the basic Cut Line tool. To activate a cut, you need to first select one of the options listed below, and then click on the Cut Line tool.

• Show Moment About Cut Line tool; this button will display the distribution of the moment about a cut line along with the integral of that distribution. The distribution of the moment generally will not match the contour you have on display, since the contour might have been selected to display a different quantity, such as deflection.

• Show Axial Force Across Cut Line tool; this button displays the distribution and total value of inplane axial force on the section. In prestressed structures, this tool can be used to view the axial force on the section.

• Show Vertical Shear Along Cut Line tool; this button displays the shear normal to the plane of the slab. This is the shear commonly checked in the typical design of beams and slabs.

• Show Distribution of Contour Quantity Along Cut Line tool; this button displays the distribution along a cut line of the quantity being displayed by the contour. For example, if the contour shows vertical deflection, activating this button will show the distribution of vertical deflection. Note that there is no integral value associated with this button.

2 “Structural Modeling and Analysis of Concrete Floor Slabs” Concrete International, American Concrete Institute, December 2005

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Select the Show Moment About Cut Line tool, followed by the Cut Line ( ) tool and then click at two ends of a cut line. A diagram similar to Fig. 4.4-1 appears. The distribution displayed is the moment in the slab about the cut line. The graphical distribution shown does not include the moment from the beam stems, if the cut includes one. The total moment about the cut line will obviously include the contribution of beam stems, if present. Also, if the cut is across steps in the slab, there will be contributions from the axial forces in the slab and the beam to the total moment about the cut line. The numerical value shown next to each distribution accounts for the contribution of all the forces to the total moment about the cut line. It is the total (integral) of moments of all actions about the centroid of the cut section. This is the value that will be used for code compliance of the design. Hence, when there are steps or beams, the integral does not always add up to the area below the distribution displayed. Since the integral should include the contributions from axial forces. This is correct, realizing that each has to be interpreted within its own context. If the font of the display is not large enough, or the ordinate of the display is too small, or each time you make a cut the previous one disappears, you can adjust these settings with the Entity Display Settings , and Result Display Settings , tools at the top left of the screen.

FIGURE 4.4-1 DISPLAY OF MOMENT Myy WITH SEVERAL CUTS

5 – OBTAIN DESIGN VALUES AT SELECTED LOCATIONS

In this part we will investigate the forces in the structure at selected locations, and find the required reinforcement for each. In the general case, the program will automatically find, calculate and report all the reinforcement that is needed for a floor system, including the beams. The exercise of this section is primarily to become more familiar with the operation of the program, and how best to spot check a location of your interest.

• Quit the viewer and go back to the Builder screen. • From the Builder screen and FEM pull-down menu, select Create Design Sections

Manually, as shown in Fig. 5-1.

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FIGURE 5 -1 VIEW OF FEM PULL DOWN MENU

• Draw two vertical cuts over the slab; one at the face of the top right column and the other at about midspan of the upper columns, as shown in Fig. 5-2. The short line segments with half arrows appearing across the cut line show the direction of reinforcement the program is going to report. If the short line segment does not appear, you need to activate it as follows: Go to the Select/Set View Items tool, and from the Finite Element tab select the check box of Symbol of Manual Design Section.

• Click on the FEM menu item Design the “Design Section(s)”. The program will calculate the resultant of the six actions at the centroid of each of the cut sections, along with the reinforcement needed to resist the moment about the cut section.

• Double click on one of the cut lines and a dialog box, as shown in Fig. 5-3.. This figure refers to the section located near the midspan. The Action at Centroid of Section gives the resultant of the six actions at the section centroid for the load combination displayed in the combo box under Actions. The figure shows the load combination Service_Combination. To see the actions for strength combinations, select that combination from the combo box items under Actions. These are the actions for which the section must be designed. However, the reinforcement reported in the lower half of the dialog window is the envelope of all load cased defined by you. You can also view the reinforcement required for each load combination, but not in this dialog box. The steps for viewing the reinforcement for each combination will be explained later.

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FIGURE 5-2 DISPLAY OF THE USER-SELECTED SECTIONS (CUTS)

(a) American units

(b) SI units

FIGURE 5-3 ACTIONS AND REINFORCEMENT OF A DESIGN SECTION It is also possible to display the area of reinforcement required for each of the sections on the screen. To display the reinforcement do the following.

• Click on Select/Set View Items tool ( ). In the Finite Element tab, select the check box of Symbol of Manual Design Section. The required reinforcement will be shown on the plan as similar to Fig. 5-4.

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(a) American Units (b) SI units

FIGURE 5-4 DISPLAY OF THE USER-SELECTED SECTIONS (CUTS)

6 – CREATE SUPPORT LINES; LOAD PATH DESIGNATION

The specification of “Support Lines” determines the direction along which the reinforcement will be placed. This is typically along the lines of columns (lines of support). In this tutorial we specify the load path along the X-direction of the slab and determine its reinforcement. In an actual design, a similar operation must be carried out along the Y-direction.

The load path consists of selecting support lines, and assigning a tributary to each of the support lines. When completed, each part of a floor must have been assigned to a support line to carry its load. For the four columns of the structure at hand, two support lines in the X-direction can be identified. We are going to use the Support Line Wizard tool to generate them automatically. Support lines can also be generated manually. Further, a support line generated either automatically or manually can be modified. In general, however, it is easiest to let the program generate them automatically.

The wizard works by searching for columns and walls along a slab band defined by you. It connects the supports detected within the band together to form a support line. The direction and width of the slab band, within which supports will automatically be sought and connected, will be defined by you. Here is how it works:

• From the Model Strips pull down menu items, click on the Support Line Wizard tool.

The dialog box shown in Fig. 6-1 opens. • In the Support Line dialog box select:

o X-Direction from the combo box. o For the band width to seek supports select 3 ft (1m).

• In large floor areas, it may become necessary to define support lines that terminate within the interior of a slab. That is why in the next input cell, Length to search for supports, there is a maximum length along which we expect the program to seek a support. In this case, we specify a length much longer than the length of the structure (300 ft; 100 m), since the floor slab is simple.

• The input cell, Angle for Wall modeling considers whether a wall encountered within the slab band of a support line should be considered to fall along the support line, or the support line should cross it. If the angle between a wall and direction of the band exceeds the value entered in the data cell (30 degrees shown in the figure), the

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support line will cross it. Otherwise, the support line will pass along the wall. Since we do not have a wall in this structure, the value entered in this data cell is of no consequence.

(a) American units

(b) SI units

FIGURE 6-1 DIALOG BOX OF SUPPORT LINE WIZARD

• Press OK to close the Support Line Wizard dialog window. The command line (the

line at the bottom of your screen) instructs you to select two points, one after the other, to identify the direction of the support line. Click at two points, one next to each of the upper two columns. An image similar to Fig. 6-2 appears. Since the scanning area displayed contains the two columns, which we intend to act as supports, click on Yes in the dialog box. The dialog box closes and the screen displays the support line selected for the top two columns as shown in Fig. 6-3. Note that this figure also shows the support lines for the lower two columns that we are going to create next.

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FIGURE 6-2 PARALLEL LINES SHOWING THE SLAB BAND FOR POTENTIAL SUPPORTS

FIGURE 6-3 SUPPORT LINE ALONG X-DIRECTION

o Repeat the same for the second support line covering the lower two columns.

This completes the creation of support lines for the X-direction. We will not discuss the creation of support lines in the Y-direction in this tutorial.

Hint: As an alternative to the automatic generation of support lines, you can also create the second support line manually. • From the Model Strips pull down menu items, click on the Create

Support Line tool. • In creating a support line manually, it is critical that you snap the support

at the center of columns and walls you identify as supports. If you do not snap at these supports, the program will disregard them. Also, you must snap at the edges of the floor slab boundary for the program to recognize where the support line starts. There are tools that make this operation simple. We will describe and use these tools next.

• Use the Snap to Nearest ( ?? ) tool and click near the edge of the slab.

The support line will pick the Slab edge; or For columns and end of walls, we must use the Snap to Endpoint ( ) tool. • Select the Snap to nearest tool. • Click to the left side of the slab edge, where you want the support line to

start. • Select Snap to Endpoint ( ) tool and deselect all other snapping tools. • Snap to the endpoint of the first column from the left. • Snap to the endpoint of the second column from the left. • Select the Snap to nearest tool and deselect all other snapping tools. • Click to the right side of the slab edge.

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• Press the “C” key to close the support line. The Support Lines generated in the X-direction should resemble those shown in Fig. 6-4.

FIGURE 6-4 SUPPORT LINES ALONG X-DIRECTION

Note At this stage in the modeling and design process we reach the point where we decide to continue the design using either the Strip Method (EFM), or the Finite Element Method (FEM). The strip method uses ADAPT-PT/RC. The finite element method uses Floor-Pro. We will continue using the finite element features of the program. Subsequently, we will come back and pick up the design from this stage and continue it using the strip method.

7 – CREATE DESIGN SECTIONS AUTOMATICALLY Each Design Strip is broken down into spans and cantilevers, if applicable. Each span and cantilever is designed at several points along its length. At each design point along a support line, a design section is automatically created. A design section is a section (cut) normal to the support line and extends on each side of the support line to the next tributary or slab edge. The number of design sections for each span has a default value between 6 and 12, but can be changed. In addition to the specified number of design sections, the program automatically selects a number of design sections at specific locations. These are at each face of column, at the end of each wall, and at midspan. For each span or cantilever, the design sections are equally spaced. Also, to avoid excessive output, the automated generation checks the spacing between design sections against a default minimum spacing3.

• Click on Generate Design Sections Automatically tool from the FEM pull down menu shown in Fig. 7-1.

3 The minimum spacing is set in the initialization file of the program. It is editable by the user.

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FIGURE 7-1 FEM PULL DOWN MENU

• Design Sections will be created automatically. Fig. 7-3 shows an example of

the Support Lines and the associated Design Strips. If the image does not appear, click on Display Design Sections button. This tool is accessible from the Support Line Result Scale Toolbar shown in Fig.7-2 below.

FIGURE 7-2 SUPPORT LINE DESIGN TOOLBAR

FIGURE 7-3 FLOOR SLAB SHOWING THE DESIGN STRIPS AND THE DESIGN SECTIONS

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8 – DESIGN THE DESIGN SECTIONS

• Click on the Design the “Design Section(s)” button to calculate the design values and the associated reinforcement for each of the Design Sections shown.

The program automatically calculates the integral of the actions for each of the Design Sections (cuts) and applies the integral to the cross-sectional area of that section to determine the required reinforcement.

The design moment (the integral value used for the computation of the reinforcement) for each of the support lines, as well as other actions, such as shear and axial forces, can be viewed for each Support Line. They can also be included in the reports that the program generates. We will now view one display variation of the design moments of the support lines in X-direction.

• Click on Display Design Section tool ( ) to turn the design sections off. • Click on the Display Graphically tool ( ) to display the moment diagram along

each of the support lines. • Click on Top-Front-Right View to see the structural in 3D.

• Click on Perpendicular Projection tool ( ) to see the distribution normal to the slab.

• Use the scaling tools ( ), if the distribution shown is not to scale.

• Use the Display Max/Min Values ( ) to see the largest and smallest magnitudes of the moments.

By now you should have obtained a diagram of moment distribution somewhat similar to Fig. 8-1.

FIGURE 8-1 DISTRIBUTION OF MOMENTS FOR DESIGN STRIPS IN X-

DIRECTION

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The reinforcement for each support line is calculated and reported. We will view the reinforcement and the design values of the upper support line.

• Click on the upper design strip. Change in color indicates that the design strip was

selected.

• Go to the results summary screen by clicking on the Show Design Summary ( ) option from the FEM pull-down menu. The result summary window with a toolbar as shown below (Fig.8-2) will open.

FIGURE 8-2 TOOLBAR OF DESIGN SUMMARY WINDOW

• Click on the Summary Report ( ) tool to see the distribution of reinforcement below

the elevation of the design strip. A diagram similar to Fig. 8-3 will appear. The diagram lists the top and bottom bars for the loading combination we selected earlier (service condition). To view the entire reinforcement necessary for the design of the design strip, select the Envelope from the combo box of the toolbar.

FIGURE 8-3 DISTRIBUTION OF REINFORCEMENT FOR

UPPER SUPPORT LINE

• From the combo box at the top of the screen select Strength Combination. Then click

on the Moment Diagram button. A distribution, such as shown in Fig. 8-4,

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appears. This diagram shows the distribution of design moment of the support line selected. It is the moment of the entire tributary shown along the support line.

FIGURE 8-4 DISTRIBUTION OF DESIGN MOMENT IN DESIGN SUMMARY SCREEN

• From the combo box at the top of the screen, select Envelope. Click on the Rebar Diagram button. The total area of reinforcement needed at each design section along the length of the support line will display, as shown in Fig. 8-5. This reinforcement is the envelope of all load cases specified by the user. In our case, we have only two load cases. Service Combination accounts for the minimum reinforcement requirements of the code.

FIGURE 8-5 ENVELOPE OF THE AREA OF REINFORCEMENT ALONG THE LENGTH OF THE DESIGN STRIP

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9 – GENERATE REBAR DRAWING

Next, we will create, view and edit the reinforcement drawing. • From the FEM pull-down menu, click on Generate Rebar Drawing. The program

generates a reinforcement drawing similar to Fig. 9-1. Obviously, when using the SI system of units, the reinforcement will be expressed in the common practice of the metric system.

o If no rebar appears on the screen, do the following:

From the User Interface pull-down menu bring the Reinforcement Toolbar on

the screen (Fig.9-2). Click on Open Rebar Display Options tool ( ) to open the window as shown

in Fig.9-3, and set the display as appropriate. If the size of the text of rebar on the screen is not right, go to the Select/Set

View Items ( ) and change the size of the Rebar font.

FIGURE 9-1 REBAR DRAWING SHOWING TOP AND BOTTOM REINFORCEMNT IN X-DIRECTION

FIGURE 9-2 REINFORCEMNT TOOLBAR

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FIGURE 9-3 REBAR DISPLAY OPTION

• Double click on one of the bars to open its property box. This allows you to modify the display, as well as other properties of the reinforcement. The extent of editing available to you depends on the configurations of your program.

• Turn the rebar display off by clicking on Display/Hide Rebar ( )

10 – DESIGN FOR PUNCHING SHEAR The next step is to check the punching shear design.

• From the FEM pull-down menu, click on Punching Shear Check. The program

performs a punching shear check, using the building code you selected. Where needed, the program provides punching shear reinforcement. It does so using the type of reinforcement you prefer4. To see the outcome of the punching shear design on the screen, again we will use the Support Line Results Scale Toolbar (Fig.10-1).

FIGURE 10-1 SUPPORT LINE RESULTS SCLAE TOOLBAR

• Click on the Display Punching Shear Design Outcome ( ) to activate the display of

punching shear results. Where punching shear does not meet the minimum requirements of the code selected by you, the column/wall will be displayed in red. Otherwise, the program places OK next to the column/wall analyzed.

• Click on the Numerical Display ( ) tool to see the punching shear stress ratios (Fig. 10-2). In the example of this tutorial, no reinforcement was needed, otherwise, the

4 You enter the type of punching shear reinforcement of your choice in one of the Criteria pull-down menu tabs.

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program would display REINFORCE next to the support, and report the amount of reinforcement.

FIGURE 10-2 PUNCHING SHEAR RESULTS

11 - REPORTS

The program generates detailed, professional-quality reports of the design you performed. You have full control of the items and the size of the report, as well as its layout. For illustration purposes, we will generate a single sheet tabular report. Refer to the Floor-Pro User Manual for details of generation of compiled reports. The tabular reports generated by the program are in RTF file format. They can be opened in any word processing program for viewing, editing and printing.

For tabular reports, we select the lower column reactions. Do the following:

• From Reports pull-down menu, select Single Default Reports/Tabular/Column

Forces/Lower Columns. A tabular report similar to the one shown below will appear.

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160.20 LOWER COLUMNS

Service_Combination

ID Label Fz Fr Fs Mrr Mss Mzz k k k k-ft k-ft k-ft

1 Column 1 -33.133 0.000 -0.000 0.474 -41.688 0.000 2 Column 2 -34.137 0.000 -0.000 -4.496 36.677 0.000 3 Column 3 -36.145 -0.000 0.000 15.101 30.699 0.000 4 Column 4 -27.532 -0.000 -0.000 12.067 -32.951 0.000

Strength_Combination

ID Label Fz Fr Fs Mrr Mss Mzz k k k k-ft k-ft k-ft

1 Column 1 -46.385 0.000 -0.000 0.664 -58.364 0.000 2 Column 2 -47.792 0.000 -0.000 -6.295 51.347 0.000 3 Column 3 -50.602 -0.000 0.000 21.141 42.978 0.000 4 Column 4 -38.546 -0.000 -0.000 16.894 -46.131 0.000

This brings us to the end of the analysis and design tutorial using the ADAPT-Floor Pro capabilities of the ADAPT software suite.

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12 – EXPORT DATA TO ADAPT-PT/RC

You can export the data generated to ADAPT-PT or ADAPT-RC for analysis and design. The following takes you through the required steps.

We start from the stage of having generated the support lines, as reproduced below from Fig.6-4.

FIGURE 12-1 SUPPORT LINES ALONG X-DIRECTION

• From Model Strips pull-down menu, click on Generate Design Strips. This will create the design strips as shown in Fig.12-2.

FIGURE 12-2 DISPLAY OF DESIGN STRIPS

The program can export the data of all the support lines of your project at one time to your hard drive. Data of each support line will be stored in a different subdirectory, ready for you to execute them one by one. But, in this tutorial we will focus on one support line only.

• Double click on the upper support line to open its property window. • Click on the teapot tool ( ) to see the design strip idealized for analysis using the

strip method. The idealized geometry will be similar to Fig.12-3.

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FIGURE 12-3 IDEALIZED GEOMETRY OF THE UPPER DESIGN STRIP

• You can view the properties of the idealized model, and edit them by clicking on the first eight tools of the Strip Model toolbar shown below (Fig.12-4).

FIGURE 12-4 STRIP MODEL TOOLS

• Click on the PT tool to open ADAPT-PT with the input data of the current design strip. Once in ADAPT-PT, view the imported data and execute the program to determine the optimum post-tensioning needed for its design.

For detailed information on how to execute ADAPT-PT refer to ADAPT-PT’s manual and its tutorials.

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APPENDIX A

DEFINITION OF ACTIONS AT CUT SECTIONS