M. To define direct analysis parameters
To define the member parameters used in an AISC 360 direct analysis, use the following procedure.
Note: The yield strength of the steel is taken from the material definition. If
the material definition is not provided for a member, then a default value of
Fy = 36 ksi is used.
- On the Loading ribbon tab, select the Direct Analysis tool in the Define Load Systems group. The Create New Load Items dialog open.
- Specify the initial τb value: Members whose flexural stiffness are considered to contribute to the lateral stiffness of the structure will have their flexural stiffness (EI) reduced by 0.8×τb .
- (Optional) Identify any axial members which contribute to the lateral stiffness of the structure:
- Click Close.
- In the Load & Definition dialog, expand the group.
- Assign each of the FLEX and AXIAL parameters listed to the corresponding members in the model.