Use the Boundary Condition Settings tab of the Structural Settings dialog to specify family symbols and adjust the spacing four each boundary condition representation.
Click Manage tab
Settings panel
Structural Settings and select the the Boundary Conditions Settings tab.
For the Fixed, Pinned, Roller, and User Defined boundary condition states, there are four symbols that are pre-loaded in structural templates. These families can be duplicated and edited to meet your display standards or needs.
Specify the desired distance in the Area and Line Symbol Spacing field to complete the Boundary Conditions settings.