beam Module

Inheritance diagram of pyNastran.bdf.cards.elements.beam
defines:
  • CBEAM

  • BEAMOR

class pyNastran.bdf.cards.elements.beam.BEAMOR(pid, is_g0, g0, x, offt='GGG', comment='')[source]

Bases: pyNastran.bdf.cards.base_card.BaseCard

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BEAMOR

PID

G0/X1

X2

X3

OFFT

BEAMOR

39

0.6

2.9

-5.87

GOG

classmethod _init_from_empty()[source]
classmethod add_card(card, comment='')[source]
raw_fields()[source]
type = 'BEAMOR'
write_card(size: int = 8, is_double: bool = False) → str[source]

Writes the card with the specified width and precision

Parameters
sizeint (default=8)

size of the field; {8, 16}

is_doublebool (default=False)

is this card double precision

Returns
msgstr

the string representation of the card

class pyNastran.bdf.cards.elements.beam.CBEAM(eid, pid, nids, x, g0, offt='GGG', bit=None, pa=0, pb=0, wa=None, wb=None, sa=0, sb=0, comment='')[source]

Bases: pyNastran.bdf.cards.elements.bars.LineElement

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CBEAM

EID

PID

GA

GB

X1

X2

X3

OFFT/BIT

PA

PB

W1A

W2A

W3A

W1B

W2B

W3B

SA

SB

or

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CBEAM

EID

PID

GA

GB

G0

OFFT/BIT

PA

PB

W1A

W2A

W3A

W1B

W2B

W3B

SA

SB

bit is an MSC specific field NX 2020 added offt

Adds a CBEAM card

Parameters
pidint

property id

midint

material id

nidsList[int, int]

node ids; connected grid points at ends A and B

xList[float, float, float]

Components of orientation vector, from GA, in the displacement coordinate system at GA (default), or in the basic coordinate system

g0int

Alternate method to supply the orientation vector using grid point G0. Direction of is from GA to G0. is then transferred to End A

offtstr; default=’GGG’

Offset vector interpretation flag None : bit is active

bitfloat; default=None

Built-in twist of the cross-sectional axes about the beam axis at end B relative to end A. For beam p-elements ONLY! None : offt is active

pa / pbint; default=0

Pin Flag at End A/B. Releases the specified DOFs

wa / wbList[float, float, float]

Components of offset vectors from the grid points to the end points of the axis of the shear center

sa / sbint; default=0

Scalar or grid point identification numbers for the ends A and B, respectively. The degrees-of-freedom at these points are the warping variables . SA and SB cannot be specified for beam p-elements

commentstr; default=’’

a comment for the card

offt/bit are MSC specific fields
Area()[source]

returns the area of the element face

Centroid()[source]
G0() → int[source]

gets G0

Ga() → int[source]

gets Ga/G1

Gb() → int[source]

gets Gb/G2

Mid()[source]
Nodes()[source]
Nsm()[source]

Placeholder method for the non-structural mass, \(nsm\)

classmethod add_card(card, beamor=None, comment='')[source]

Adds a CBEAM card from BDF.add_card(...)

Parameters
cardBDFCard()

a BDFCard object

beamorBEAMOR() or None

defines the defaults

commentstr; default=’’

a comment for the card

center_of_mass()[source]

the centroid formuala is way more complicated if you consider the nonstructural mass axis

center_of_mass_xform()[source]

A B ———- ^ ^ | wa | wb | | 1———-2

1-2 are the nodes of the bar A-B defines the axis of the shear center

^ z

+–+ | | | | | | 2—> y | +–+ | | +—–+

cross_reference(model: BDF) → None[source]

Cross links the card so referenced cards can be extracted directly

Parameters
modelBDF()

the BDF object

classmethod export_to_hdf5(h5_file, model, eids)[source]

exports the elements in a vectorized way

property ga
property ga_ref
property gb
property gb_ref
get_axes(model: BDF) → Tuple[Any, Any, Any, Any, Any][source]

Gets the axes of a CBAR/CBEAM, while respecting the OFFT flag.

Notes

pyNastran.bdf.cards.elements.bars.rotate_v_wa_wb() for a description of the OFFT flag.

is_passed: bool out: (wa, wb, ihat, jhat, khat)

get_axes_by_nodes(model: BDF, pid_ref, node1, node2, xyz1, xyz2, log)[source]

Gets the axes of a CBAR/CBEAM, while respecting the OFFT flag.

Notes

pyNastran.bdf.cards.elements.bars.rotate_v_wa_wb() for a description of the OFFT flag.

get_edge_ids()[source]

Return the edge IDs

get_offt_bit_defaults()[source]

offt doesn’t exist in NX nastran

get_orientation_vector(xyz)[source]

Element offsets are defined in a Cartesian system located at the connecting grid point. The components of the offsets are always defined in units of translation, even if the displacement coordinate system is cylindrical or spherical.

For example, in Figure 11-11, the grid point displacement coordinate system is cylindrical, and the offset vector is defined using Cartesian coordinates u1, u2, and u3 in units of translation.

get_x_g0_defaults()[source]

X and G0 compete for the same fields, so the method exists to make it easier to write the card

Returns
x_g0varies

g0 : List[int, None, None] x : List[float, float, float]

Notes

Used by CBAR and CBEAM

property is_bit

is the bit flag active?

property is_offt

is the offt flag active?

property node_ids
raw_fields()[source]
repr_fields()[source]

Gets the fields in their simplified form

Returns
fieldsList[varies]

the fields that define the card

safe_cross_reference(model: BDF, xref_errors)[source]
type = 'CBEAM'
uncross_reference() → None[source]

Removes cross-reference links

validate()[source]

card checking method that should be overwritten

write_card(size: int = 8, is_double: bool = False) → str[source]

Writes the card with the specified width and precision

Parameters
sizeint (default=8)

size of the field; {8, 16}

is_doublebool (default=False)

is this card double precision

Returns
msgstr

the string representation of the card

write_card_16(is_double=False)[source]
pyNastran.bdf.cards.elements.beam._init_offt_bit(card, unused_eid: int, offt_default)[source]

offt doesn’t exist in NX nastran