STAAD.Pro can now graphically define spring supports that are to allow tension only or compression only forces.

The Tension/Compression Only Support command is created from the Supports dialog box.

The Supports dialog can be accessed from the General | Support page in the Modeling mode.

Click on the Create button and select the Tension/Compression Only Spring sheet thus

The selection of Reaction Type indicates that if, after any of the cycles of analysis, the direction of the force in the spring is of the wrong ‘type’, then the support will be removed from that direction and a new analysis performed.

This support definition should be either ‘added’ to the Supports dialog (by clicking on the Add button) or assigned to the currently selected nodes (by clicking on the Assign button) that have previously been assigned with spring supports. If the support is not assigned as it is created, it can be assigned later from the Support dialog. However, note that if it is not assigned to at least one spring support when STAAD.Pro is closed, then the definition will not be saved in the STD file.