Star Seismic Buckling Restrained Braces

Star Seismic^® brace sizes can be assigned by selecting Assign > Braces > Size. This opens the Assign Brace Size dialog that contains specific Star Seismic Buckling Restrained Braces (BRB) sizes.

When a Star Seismic size is assigned, the brace is automatically tagged as a "Buckling Restrained Brace". It is not necessary to explicitly designate as the brace as a BRB, nor is it necessary to assign an Axial Stiffness Modifier; that is done automatically by the program.

The design criteria for Star Seismic buckling restrained braces can be defined by selecting Criteria > Buckling Restrained > Star Seismic. This is also referred to as global setting for all Star Seismic BRBs in the model and it applies to all Star Seismic BRBs. The Star Seismic Criteria dialog contains global settings. Note that the Minimum Clearance refers to the distance between the column and beam flanges and the end of the brace.

It is also possible to assign specific values to specific braces, on a brace-by-brace basis, by selecting Assign > Braces > Buckling Restrained > Star Seismic.

Note: This command can be used to assign a specific Stiffness Modifier value to the brace, although it is generally not necessary since the program automatically calculates that value.

Star Seismic Buckling Restrained Brace File

The file RAMStarSeismic.ssd contains proprietary information for each Star Seismic BRB size.

Analysis with Star Seismic BRBs

Select View > Members to view what is assigned to each Star Seismic BRB for the Stiffness Modifier, whether it is a calculated value or an assigned value. If the program is using a calculated value, the label will have a "Calc" prefix followed by the calculated value in parentheses.

When the analysis is performed, the Stiffness Modifiers are applied accordingly. The Member Forces report is enhanced to include pertinent Star Seismic brace information, including the Stiffness Modifier. When the Calculated value is used, it is listed; when a user-defined value has been assigned, both the calculated and the user-defined values are listed, along with the ratio of the user-defined to calculated values.

In addition to the standard provisions of the steel specification, there are additional seismic requirements per AISC 341; those provisions are checked in the RAM Frame Steel Seismic Provisions module for Star Seismic buckling restrained braces.