PBEAML

Geometric properties Element

Description

PBEAML lets you specify the geometric properties for an associated beam element of a specific cross section type.

Format

<PBEAML

id = "integer"

mid = "integer"

type = "string"

dim1a = "real"

dim2a = "real"

dim3a = "real"

dim4a = "real"

dim1b = "real"

dim2b = "real"

dim3b = "real"

dim4b = "real"

nx = "integer"

ny = "integer"

nz = "integer"

ngx = "integer"

ngy = "integer"

ngz = "integer"

graph = "integer"

Attributes

Unique beam property identification number.

mid

Material property identification number.

dim1a, dim2a, dim3a, dim4a

Dimensions of the beam at the 1st node of the element.

type

Specifies the type of cross-section for this beam.

Choose from the following options:

BAR, BOX, BOX1

CHAN, CHAN1, CHAN2, CROSS

H, HAT, I, I1, L, T, T1, T2 and Z

See Comment 4 for more details on the cross-section types.

dim1b, dim2b, dim3b, dim4b

Dimensions of the beam at the second node of the element.

nx, ny, nz

Number of integration points in the X, Y and Z directions.

Default for nx is 5, ny is 3 and nz is 3.

ngx, ngy, ngz

Number of sub-elements in the X, Y and Z directions. The default for all three is 1. See Comment 5 for more details.

graph

A post-processing flag that determines how this element is represented in the animation H3D. The default is 2. See Comment 5 for more details.

Comments

1.	This type of property card is used to specify the geometric properties of the BEAM element. Each beam property element must have a unique identification number.

2.	This property card defines the geometrical properties of the beam. The material properties of the beam are defined by the material specified by mid.

If only the dimensions at the start of the beam element are specified, MotionSolve assumes the cross section of the beam to be constant. However, if additionally, dimensions at the end of the beam element are specified, then these dimensions are varied linearly from node 1 to node 2 to represent the beam in the animation H3D.

4.	The attribute type defines the type of cross section for this beam element. You may choose from the following types:

Type	Cross section	Required Inputs	Default
BAR		dim1a, dim2a	dim1b = dim1a, dim2b = dim2a,
BOX		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
BOX1		dim1a, dim2a, dim3a, dim4a dim5a, dim6a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a, dim5b = dim5a, dim6b = dim6a
CHAN		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
CHAN1		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
CHAN2		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
CROSS		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
H		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
HAT		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
I		dim1a, dim2a, dim3a, dim4a dim5a, dim6a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a, dim5b = dim5a, dim6b = dim6a
I1		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
L		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
T		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
T1		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
T2		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a
Z		dim1a, dim2a, dim3a, dim4a	dim1b = dim1a, dim2b = dim2a, dim3b = dim3a, dim4b = dim4a

5.	graph is a post-processing flag that determines how this element will be represented in the animation H3D file.

•	graph = “0” implies that this element will not be represented in the H3D

•	graph = “1” implies that this element will be represented as a line drawn between the two connecting nodes.

pbeaml_fig17

Figure 1: The representation of a beam with graph = 1.

Note: When using graph=”0” or graph=”1”, you will not be able to visualize the stress, strain or displacement contours. To do this, use graph=”2” or graph=”3”.

•	graph = “2” implies that the beam will be represented by 3D solid elements. This mode is useful when trying to visualize the stress/strain and displacement contours.

Figure 2: The representation of a beam with graph = 2. The beam is represented by 3D elements

•	graph = “3” implies that the beam is represented both as 3D solid elements as well as a line connecting the two nodes of the beam. This is useful when you need to visualize both the center line and the 3D representation of the beam.

pbeaml_fig19

Figure 3: The representation of a beam with graph = 3. The 3D elements in the middle of the beam are turned off to show the center line of the beam

When representing the beam as a solid, the arguments ngx, ngy and ngz determine the number of elements that are used to represent the beam in the animation H3D.

pbeaml_fig20

ngx = ngy = ngz = 1

pbeaml_fig21

ngx = ngy = ngz = 2

pbeaml_fig22

ngx = ngy = ngz = 3

Figure 4: Effect of ngx, ngy and ngz on the 3D representation of a simple beam

While increasing the ngx, ngy and ngz results in a better representation of the beam, it also increases the post-processing time taken by MotionSolve to write out the H3D. In addition, large values of ngx, ngy and ngz will increase the file size of the H3D considerably. Consider using the minimum values of these attributes that satisfy your visualization needs.

Example

The example demonstrates the definition of a PBEAML property element.