Staged Material Properties

In RS3 the properties of a material can be modified at different stages of a multi-stage model, by using the Staging option in the Material Properties dialog. This allows you to simulate, for example:

• an increase or decrease in material stiffness
• an increase or decrease in material strength

as staging progresses. The material properties can be increased or decreased by user-defined factors at different stages, as described below.

To stage material properties:

1. In the Material Properties dialog, select the Staging tab.
2. Select the Stage Strength/Stiffness checkbox.
3. In the Stage Material Properties table, select the Add Stage button, until the number of rows in the table, is equal to the number of stages for which you need to modify the material properties. For example:
   
   1. If you need to modify material properties at 3 different stages, then select Add Stage twice, so that a total of 3 rows appears in the table.
4. In each row, enter the Stage number at which the properties are to be modified.
5. In each row, enter the required Factor(s) that will be used to modify the indicated material parameter(s).
   
   • The Factors are multiplied by the parameter values in the Material Properties dialog, in order to obtain the actual value to be used for a parameter, at a given stage of the analysis
   • For example: if you want to increase Young’s Modulus by 20%, enter a Factor of 1.2 for Young’s Modulus, at the desired stage(s)
   • Leave the Factor = 1 for any parameter that does not change value
6. It is important to note that you only need to define the stage and factor information, for the stages at which you want to modify properties. You do not need to define this information at stages where the properties do not change.
7. If you accidentally add too many rows with the Add Stage button, click the mouse on the row number and select the Delete Stage button, to delete the row.
8. When you are finished entering all stage numbers and factors, select OK in the Material Properties dialog when you are finished defining all materials.

When the analysis is run, RS3 will use the factors in the Stage Material Properties table, to determine the material properties to be used at each stage of the analysis, for a given material.

Reset Element Stress When Material Changes

In RS3 it is possible to assign a new material type to any region of the model at any stage. There are various modeling scenarios in which this can be used. When you change the material type of a solid element, normally the initial stresses in the element are reset to zero. This is the default setting for this option (i.e. the checkbox is selected). If you do not wish to reset element stresses when the material type is changed, you can turn this checkbox off.