Vertex Attributes: Non-structural Mass

Description

Assigns non-structural mass to selected vertices using a scalar mass value, a dynamic amplification factor and an optional offset from the vertex.

When the geometry is meshed, the node created at the vertex will inherit the non-structural mass attribute (see Node Attributes: Non-Structural Mass).

Vertex non-structural mass attributes are not interpolated along edges during meshing.

Non-structural mass is similar to translational mass, except that it is load case dependent.

Dialog

Mass

Scalar value of mass.

Dyn Factor

Scales the mass value in dynamic analysis and, optionally, in the linear seismic load cases.

ID

Assigns an ID to the attribute.

By using different IDs, multiple non-structural mass attributes can be defined at the same vertex for the same load case.

Offset (X/Y/Z)

Three components that define the magnitude and direction of the offset of the mass from the vertex.

A mass offset is often used to consider accidental torsion effects in the dynamic analysis of buildings.

Coordinate System

The coordinate system (UCS) in which the offset components are defined.

The UCS is used only to define the global Cartesian components of the offset. Subsequent changes to the UCS do not affect the offset location.

Common Controls

Units

Mass (e.g., kg, tonne, lb).

See Also