Beam Attributes: Principal/Local Distributed Force

Description

Assigns distributed forces in the principal axes to selected beam elements.

The distribution can be constant, linear, triangular or trapezoidal. It may act over the whole or a partial length of the element, in any of the element's local or principal axis directions.

A positive distributed force acts in the positive direction of the principal axis.

Principal distributed force attributes are load case dependent.

Dialog

P1 / P2 / PA / PB

Value of distributed force at different points along the element. The force is linearly interpolated between these points.

P1

Distributed force value at end 1.
P2

Distributed force value at end 2.
PA

Distributed force value at position a.
PB

Distributed force value at position b.

a / b

Distance of points PA and PB from each end, specified as a fraction of the element's length.

Non-dimensional values in the range 0 to 1.

a

Relative distance from end 1 of the element. Determines the position of PA. At end 1, a=0.0.
b

Relative distance from end 2 of the element. Determines the position of PB. At end 2, b=0.0.

Dir 1 / 2 / 3 / x / y /1-2 / x-y

The principal axis direction in which the distributed force acts. See Beam Elements: Local and Principal Axes.

Dir 1-2 and Dir x-y define the load direction at an angle in the principal 1-2 plane or local x-y plane, respectively. This is a convenience feature of the dialog for assigning the load in a direction not parallel to the axes. Once applied, the load is converted to components parallel to the directions of the axes and assigned as two separate loads in the respective axes.

θ-1 / θ-x

The angle that defines the load direction, measured from the principal 1 or local x axis, when Dir 1-2 or Dir x-y, respectively, is selected.

Swap

Swaps the values of a and b, P1 and P2, PA and PB.

Assigns an ID to the attribute.

By using different IDs, multiple forces can be applied to the same element for the same load case.

IDs are positive integers between 1 and 192.

Distribution Type

The distribution type includes constant, linear, triangular and trapezoidal over the whole or partial length of the element.

The appropriate text boxes will be active depending on the force distribution selected.

Common Controls

Units

Components: Force/Length (e.g., N/m, lbf/in).

Relative Distances: Dimensionless.