You can clean up the current job by clicking the toolbar button or selecting "Clean-up Job" from the File menu or the popup menu.
Cleans up your model by deleting obsolete items or items that are no longer connected to anything. For example, it will remove loads that are applied to non-existent nodes, members or plates, or section properties that are not being used by any members. It is very useful for quickly removing the causes of many analysis errors.
The clean-up tool can also merge nodes that are within a specified distance of one another, transferring members, plates, restraints, loads, etc. from the deleted nodes to the retained nodes. If this action results in a change to the way the structure responds to the applied loads then an error message will be displayed and the clean-up will not proceed. Any pairs of nodes close together that are linked with master-slave constraints will not be merged.
Dummy nodes can be removed provided they are not used as direction nodes for members or plates.