Struct ForceBeamColumn3 

pub struct ForceBeamColumn3 {
    pub node_i: Node3Id,
    pub node_j: Node3Id,
    pub g: f64,
    pub j: f64,
    pub density: f64,
    /* private fields */
}

ForceBeamColumn’s spatial (biaxial) counterpart: a 2-node, force-based 3D beam-column. Basic system, force interpolation, and state- determination algorithm are the direct biaxial generalization of ForceBeamColumn’s (see that type’s doc comment for the algorithm itself, ported unchanged in structure — only NSD/NBD and the matrices below grow); torsion is excluded from the basic system and handled as a decoupled elastic G*J/L term, same as DispBeamColumn3.

Basic system, v = [v1..v5]: v1 axial elongation (same as ForceBeamColumn’s v1); v2/v3 the z-bending chord-relative end rotations, numerically identical in form to ForceBeamColumn’s v2/v3 since local z-bending uses the same [v, rz] convention; v4/v5 the y-bending chord-relative end rotations, built by substituting theta_equiv = -ry into the same construction (matching DispBeamColumn3::strain_displacement’s b_kappa_y substitution) — this flips the sign of v4/v5’s rotation coefficient relative to v2/v3’s (their translation coefficients are unchanged, since the chord slope psi is purely geometric and doesn’t depend on the rotation sign convention). Basic forces q = [q1..q5] are then automatically work-conjugate to v by construction (A/A^T share the same matrix — the standard force-method contragredience), with q1=N, (q2,q3) conjugate to (Mz’s end values), (q4,q5) conjugate to My’s. This whole construction — not just guessed by analogy — is verified against ElasticBeamColumn3’s exact biaxial-bending elastic stiffness in core/tests/elements/force_beam.rs, the same role core/tests/elements/force_beam.rs plays for the planar element.

Fields

node_i: Node3Id

node_j: Node3Id

g: f64

j: f64

density: f64

Mass per unit volume, same convention as ForceBeamColumn::density.

Implementations

impl ForceBeamColumn3

pub fn new( node_i: Node3Id, node_j: Node3Id, g: f64, j: f64, vec_xz: [f64; 3], fibers: Vec<Fiber3>, integration: BeamIntegration, ) -> Self

pub fn with_density(self, density: f64) -> Self

pub fn fiber_responses(&self) -> Vec<Vec<(f64, f64)>>

See ForceBeamColumn::fiber_responses’s doc comment — same contract, biaxial e_commit.

Trait Implementations

impl Clone for ForceBeamColumn3

fn clone(&self) -> ForceBeamColumn3

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ForceBeamColumn3

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.