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Bottom Chord

bridge.superstructure.truss_member.bottom_chord

publishedEdit

Definition

Bottom Chord forming part of the truss load path.

Class kind: component
Abstract: no
Depth: 5
Origin: reference source
Ontology: engineering-reference-book.bridge v1.0.0
Aliases: Lower Chord
Abbreviations: —
Last changed: 7/27/2026, 2:50:05 PM

Identification

Positive labels: Bottom Chord, Lower Chord
Negative labels: —
Visual features: linear steel member within triangulated truss
Min identity clues: 2

Evidence

Preferred views: elevation, detail, steel_schedule
Evidence types: view, detail, schedule, note, dimension, level, section_callout
Source trace required: yes

Measurements (5)

Name	Symbol	Unit	Required
Length	`L`	m/mm	required
Cross-sectional Area	`A`	m2/mm2	required
Instance Count	`N`	count	required
Steel Grade	`fy`	—	required
Mass	`M`	kg/t	required

Relationships (1)

part_ofbridge.superstructure.main_load_system.truss

BOQ items (1)

Item code	Formula	Result	Unit
`bridge.steel.truss.bottom_chord.mass`	`M`	mass	t

Validation

Blocking if missing: yes
Human review allowed: yes

no_evidence_no_number
retain_document_page_bbox_and_evidence_id
do_not_mix_drawing_revisions
do_not_average_conflicting_values
prefer_explicit_labels_over_shape_only
match_plan_elevation_and_section_when_applicable

Provenance

Basis: engineering_reference
Project values included: no

Children (0)

None — this is a leaf class and can be deleted.