Virtual work diagrams display the percentage of virtual work of an element relative to the balance of the structural members. It can be used to reduce structural deflection by indicating which elements have the highest percentage of energy and thus will most affect the deflection if their stiffnesses were to be modified.
Click the Display menu > Show Virtual Work Diagram command to access the Virtual Work Diagram form.
On that form, select the Forces and Displacements load cases, and the Value Type to be displayed.
Click the OK button to display the percentage of energy the element is experiencing relative to the other elements in the structure.
Example: If the user is interested in reducing the roof story drift resulting from a wind load, a wind load case is selected for the Force. For Displacement, a load case is used that has lateral forces only at the roof level even though the real displacement is caused by a distributed wind load. The structure is then displayed with the percentage of virtual work energy that the element is experiencing from the stresses induced by the Force load case and the displacement from the Displacement load case. Essentially, this means that when the stiffness of an element with a higher percentage is modified, the deflection of the structure is more affected than if the stiffness of a lower percentage element is modified.