New Model

Forms: Model Initialization, New Model Quick Templates

The File menu > New Model command or the New Model button can be used to start a new ETABS model. The basic process for creating a new model involves  initializing the mode with the display units, a default section database, and  the design codes, which determines the default definitions  to be used (i.e.,  all properties, loads, load cases,and the like). After the model has been initialized, the layout and  the structure for the model are defined.  Throughout the startup process, default values are provided such that little more than clicking a few OK or Apply buttons is required to create the model file. More typically, the default values would be modified as the process proceeds, to specify the particular characteristics of a model.  The following numbered items step through the model start up process.

1. Click the  File menu > New Model command or the New Model button to access the Model Initialization form. Choose an option to determine the system of units to be used and the initial definitions of all properties, loads, load cases,and the like -- everything except the grids, objects, and assignments to the objects:

Note:   Place the cursor over the  and hover text providing a brief explanation of the option will display. In the case of the Display Units, a table of the current units will display.   

• • Use Saved User Default Settings option. This option includes the Display Units, the Preferences (including the Steel Section Database and the Steel and Concrete Design codes), the Properties (i.e., materials, frame sections; slab, deck and wall sections; springs and diaphragms and so on) and Definitions (i.e., functions, load patterns, load cases, load combinations and so on). This option is similar to the next option, Use Settings from a Model File, except this option make the availability of an entire model file unnecessary.

Note: The User Default Settings are saved using the Options menu > Save User Default Settings command. Thus, if this is the first time the program is being used, no saved user default settings are available; therefore, in such a case, it is recommended that the Use Built-In Settings With option be used (see below).

1. • Use Settings from a Model File option. When this option is selected, a form displays that can be used to locate the .edb file from which are obtained the settings upon which to base  the new model. Similar to the Use Saved User Default Setting option, the settings include the Display Units, the Preferences, the Properties and the Definitions. Objects and assignments from the .edb file are not used.

This method is generally preferable if sets of properties, analyses, and design definitions are to be used among projects with common characteristics. Create as many ETABS .edb files as necessary and save them to a suitable location (e.g., where all engineers have access to them, or in an area with limited access for more personalized use).

Note:  Using an existing model as the starting point for a new model is not "importing" a model. Basing a new model on an existing model means that definitions and settings (i.e., preferences) are being shared from one model to another. This differs from importing a model because an imported model can include objects and their assignments.

1. • Use Built-In Settings With option. When this option is used, specify the Display Units, the default Steel Section Database, and the codes for design of steel and concrete members.

The  built-in properties and definitions can be modified using the commands on the Define menu.

1. • • The Display Units  selected when a model is created are permanent and cannot be changed. However, this is not of any real consequence to the user because if metric units are used in a model created using US units, the metric units will always be converted to/from US units. Similarly, if the model was created using metric units and at some point for some reason US units are used, ETABS will convert the US  units to metric units (units can be changed using the Display Units form).  Note that the model will always open in the originally specified system:  US Customary or Metric. Thus, the important factor is to recognize which units are being used when entering model data or reading program output.

     • The Steel Section Database drop-down list allows selection of a library of section shapes that will then be available during the modeling process. As the names of the options suggest, the libraries contain shapes that reflect various industry standards in multiple countries (e.g., American Institute of Steel Construction, British Standards, Canadian Institute of Steel Construction, and so on). Note that additional libraries can be added to a model later using the Define menu > Section Properties > Frame Sections command and the Import New Properties button.

     • Steel Design Code and Concrete Design Code determine the default definitions  to be used (i.e.,  all properties, loads, analysis cases,and the like) for the steel and concrete components of the model design.

2. Click the OK button on the Model Initialization form to access the New Model Quick Templates form.

3. Specify the layout of the structure (grid and story dimensions) and then select a model type by clicking the appropriate button. As indicated previously, typically, these model templates would be modified as the modeling process proceeds, to reflect  the specific project  characteristics.

1. • Grid Dimensions (Plan) options.   A well defined grid system enables, for example, elevation views in the model to occur at defined grid lines; objects added to the model to be placed accurately and "snapped to" specific locations; and object to be meshed for analysis. Labeling of grid lines in the model can match the labeling on plans, making easy identification of locations within the model.

   • • Uniform Grid Spacing option. Specify the number of grid lines in the X and Y directions and a uniform spacing for those lines. Note that the uniform spacing in the X direction can be different from the uniform spacing in the Y direction. This option defines a grid system for the global coordinate system only.

Click the Grid Labels button to access the Grid Labeling Options form; use that form  to label grid lines to match labeling on plans, if desired.

1. 1. • Custom Grid Spacing option. This option allows non-uniformly spaced grid lines to be defined in the X and Y directions for the global coordinate system. Choose this option and then click the Edit Grid Data button to access the Grid System Data  form. Use that form to label grid lines, specify spacing, appearance and the like.

Regardless of which option is used to initially define grid lines, the grid lines can be edited and additional coordinate/grid systems can be defined in the model using the Edit menu > Edit Stories and Grid Systems command or the Edit menu > Edit Towers, Stories and Grid Systems command if the Options menu > Allow Multiple Towers command has been enabled.

1. • Story Dimensions options.  Choose an option for defining the number and height of the stories in the model.

   • • Simple Story Data option. When this option is selected, use the defaults or specify values for the Number of Stories, Typical Story Height, and Bottom Story Height in the edit boxes. The value specified for the Typical Story Height will be used for all stories in the model, except the bottom story. ETABS will assign default names to each story. This data can be modified later using the Edit menu > Edit Stories and Grid Systems command or the Edit menu > Edit Towers, Stories and Grid Systems command.

     • Custom Story Data option. Use this option to manually define story names, story levels of non-uniform height, and story similarity. Select the Custom Story Data option and click the Edit Story Data button to access the Story Data  form.  Click directly in the edit boxes to change any of the items.

   • Add Structural Objects buttons. Click the appropriate button: Blank,  Grid Only, Steel Deck, Staggered Truss System, Flat Slab, Flat Slab with Perimeter Beams, Waffle Slab, and Two-Way or Ribbed Slab buttons. The program will then create the model based on the template.

   • • Blank button. When the Blank button is clicked, the program opens display windows but does not load any grid or story dimension data specified by default on the New Model Quick Templates form. This option may be  ideal  when Importing a model from another program file to start  a new model.

     • Grid Only button. When this button is clicked, a grid system will be added to the model without any structural objects. Proceed to build the model using (a) the Draw and Edit menu commands to draw the structural objects, and  (b) the Import commands to import and copy geometry data from other programs and other ETABS .edb files.

4. Clicking the template button will display the Structural Geometry and Properties for {Grid Only  or Template Type} form.  Click on the hyperlinks in Step3 for more information about the Structural Geometry and Properties for {Template Type} form. In most cases, using templates to start a model is the simplest, most convenient and quickest method, although it is not necessary because the other commands in the program can be used to draw, edit, define and assign the necessary components to create a model. Using templates (i.e., not the Grid Only button) is recommended if the program is new to you.

Note: When using the ETABS concrete building templates, beams and slab ribs (joists) are normally modeled with depths equal to the dimension from the top of the slab (not bottom of slab) to the bottom of the beam or slab rib. Also note that in ETABS, beams are modeled as frame elements. Thus slabs with out-of-plane bending capability span from center-of-beam to center-of-beam in the ETABS model.