Units

You can work with imperial (kips, inches, etc.) or metric (KN, meters, etc.) units, or any combination of the two. The current units appropriate for each data item are shown at the tops of the data columns in the spreadsheets and with the plot of values in the model view.

Change Units

To change units:

  1. Click the Units icon in the ‘Model’ section of the Home ribbon.

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    The Units Selection window opens.

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  2. Specify the units you want for each item in the drop down lists.

    Standard units systems are preset and may be specified by clicking the Standard Imperial and Standard Metric buttons.

  3. (Optional) Clear the check box for Converting Existing Data if you do not wish to convert values already entered (as shown in the following image).

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  4. (Optional) Check the Set as Default box to save your selections as the default.

    You can save any of the units as the default setting so that when you start a new model the information is already there. (as shown in the following image).

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  5. Click OK to save your change and close the window.

Standard Imperial Units

This is the units system currently prevalent in the United States. 'Feet' are used for location entries such as node coordinates and load locations, and 'Inches' are used for section property entries such as area and moment of inertia. Force and weight units are in 'kips', where 1 kip = 1000 pounds. Stress units are in 'ksi' (kips per square inch).

Standard Metric Units

This units system uses 'Meters' for location entries and 'Centimeters' for section property entries. Force units are in 'kN' (kiloNewtons), where 1 KN = 1000 Newtons. Stress units are in 'MegaPascals' (MPa), where a MegaPascal is 1,000,000 Newtons per square meter. Weight units are in 'Kilograms' and thermal units are in 'Degrees centigrade.

Units Specifications

The following are the unit specifications and their applications:

Unit Specifications Measurements and Usage

Measurement Usage

Lengths

Coordinates, Unbraced Lengths, Load Locations

Dimensions

Shape Properties, Plate Thickness, Member Offsets

Material Stiffness

E, G

Weight Densities

Material Density

Forces

Loads, Forces

Linear Forces

Distributed Loads

Moments

Loads, Forces

Surface / Area Loads

Plate/Shell Surface Loads, Area Loads

Translational Springs

X Y Z Boundary Conditions

Rotational Springs

X Rot, Y Rot, Z Rot Boundary Conditions

Temperatures

Thermal Coefficient, Temperatures

Deflections

Deflections, Displacements

Stresses

Fy, Allowable and Actual Stresses