← highway ontologyHighway Asset › Pavement System
Granular Sub-base
highway.pavement_system.granular_subbasedraftEdit
Definition
Graded granular layer immediately above the subgrade.
- Class kind
- component
- Abstract
- no
- Depth
- 2
- Origin
- reference source
- Ontology
- engineering-reference-book.highway v0.1.0
- Aliases
- GSB, Sub-base
- Abbreviations
- GSB
- Last changed
- 7/27/2026, 2:50:06 PM
Identification
- Positive labels
- Granular Sub-base, GSB, Sub-base
- Negative labels
- —
- Visual features
- lowest hatched pavement band in the layer stack
- Min identity clues
- 2
Evidence
- Preferred views
- pavement_detail, typical_cross_section, pavement_layer_schedule
- Evidence types
- view, detail, schedule, note, dimension, level, section_callout
- Source trace required
- yes
Measurements (3)
| Name | Symbol | Unit | Required |
|---|---|---|---|
| Width | W | m | required |
| Thickness | T | mm | required |
| Length | L | m | required |
Relationships (1)
- placed_on
highway.earthwork_system.subgrade
BOQ items (1)
| Item code | Formula | Result | Unit |
|---|---|---|---|
highway.pavement.granular_subbase.volume | W * T * L | volume | m3 |
Facets
- grading
- grading_i, grading_ii, grading_iii, grading_iv
Validation
- Blocking if missing
- yes
- Human review allowed
- yes
no_evidence_no_numberretain_document_page_bbox_and_evidence_iddo_not_mix_drawing_revisionsdo_not_average_conflicting_valuesprefer_explicit_labels_over_shape_onlymatch_plan_profile_and_cross_section_when_applicable
Provenance
- Basis
- taxonomy_spec
- Project values included
- no
- mindmap_module_spec_taxonomy_highway
- no page list
Children (0)
None — this is a leaf class and can be deleted.