Bulk Data Entry Defines a beam element for multibody dynamics solution sequence without reference to a property entry.


(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
A I1 I2 J K1 K2


(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CMBEAM 1 2 123 125 0.0 0.0 1.0 5.0
100.0 833.3 833.3 1485.3


Field Contents SI Unit Example
EID Unique element identification number.

(Integer > 0)

MID Material identification number.

Only MAT1 material definitions may be referenced by this element.

(Integer > 0)

GA, GB Grid point identification number of connection points.

(Integer > 0; GAGB)

X1, Y1, Z1 Components of vector v at end A, measured at end A, parallel to the components of the displacement coordinate system for GA, to determine (with the vector from end A to end B) the orientation of the element coordinate system for the BEAM element.


G0 Grid point identification number to optionally supply X1, X2, and X3 (Integer > 0). Direction of orientation vector is GA to G0.

(Integer > 0)

L Undeformed length along the X-axis of the beam.


A Area of the beam cross-section.

No default (Real > 0.0)

I1 Area moment inertia in plane 1 about the neutral axis.

No default (Real > 0.0)

I2 Area moment inertia in plane 2 about the neutral axis.

No default (Real > 0.0)

J Torsional constant.

(Real > 0.0)

K1, K2 Area factor for shear.

Default = 0.0 (Real)


  1. The X-axis of the beam is always along the line connecting G1 and G2. The Z-axis of the beam is determined based on the X-axis and the Y-axis provided by G3/X1, Y1, and Z1.
  2. The moments of inertia are defined as:
    Figure 1.
    | 1 = / z z = y 2 d A | 2 = / y y = Z 2 dA
    The beam coordinates must be aligned with the principal axes of the cross-section.
  3. The transverse shear stiffness in planes 1 and 2 are (K1)AG and (K2)AG, respectively. If a value of 0.0 is used for K1 and K2, the transverse shear flexibilities are set to 0.0 (K1 and K2 are interpreted as infinite).
  4. This card is represented as a bar2 element in HyperMesh.