Mechanical APDL Structural Analysis Guide

where

Nx = Axial resultant force

Ny = Resultant force in beam Y coordinate direction

Nz = Resultant force in beam Z coordinate direction

Mx = Torque about the beam axes

My = Torque about the beam Y coordinate direction

Mz = Torque about the beam Z coordinate direction

Ax = Axial acceleration

Ay = Acceleration in beam Y coordinate direction

Az = Acceleration in beam Z coordinate direction

Rx = Angular acceleration about beam axes

Ry = Angular acceleration about beam Y coordinate direction

Rz = Angular acceleration about beam Z coordinate direction Cij( T) (where i=1,7 and j = i,7) = mass

or moment of inertia terms in the upper triangle of the cross-section mass matrix as a function of

temperature

T = Current temperature

15.5.1. Defining a Composite Beam Section

Each of the following commands specifies a particular component quantity necessary for defining a
preintegrated composite beam section:

Table 15.3: Commands for Specifying Preintegrated Composite Beam Section Data

Command Quantity Defined and Data Specified

Cross-section stiffness matrix. Upper triangle

of 6 x 6 or 7 x 7 matrix. Row and column 7 are

used only when KEYOPT(1) = 1.

CBMX [ 1 ]

Cross-section mass matrix. Upper triangle of 6

x 6 matrix.

CBMD [ 1 ]

Temperature specification for a subsequent

matrix.

CBTMP [ 1 ]

T

CBTE [ 1 ] Thermal expansion coefficient

ALPHA

1. Repeatable for six independent temperatures.

Temperature dependencies (T) You can define each of the preintegrated composite beam section
data components as temperature-dependent. It is possible to specify up to six temperatures (T ) by reis-
suing any command as necessary. If you issue a command for a temperature specified earlier, the most
recent data supersedes the previous value.

15.5.1.1. Matrix Input.

Each component (axial, bending, torque, transverse shear, and warping) of a preintegrated beam section
definition is input directly as a 7 x 7 matrix. The terms of the matrix are defined via the CBMX command.

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

Using Preintegrated Composite Beam Sections