Steel Design Glossary — Structural Engineering Terms
A comprehensive reference of 100+ structural steel engineering terms. Each entry provides a clear definition with practical design context across AISC 360, AS 4100, EN 1993, and CSA S16.
Key Terms
- Allowable Stress Design (ASD) — Traditional design method using service loads and a factor of safety. Still used in some jurisdictions and for serviceability checks.
- Bearing-Type Connection — Bolted connection where load is transferred through bolt bearing against the connected plies. Most common connection type in structural steelwork.
- Block Shear Failure — Failure mode involving rupture of a block of material around a bolt group, combining tension and shear failure planes.
- Camber — Upward curvature intentionally introduced in a beam during fabrication to counteract dead load deflection.
- Capacity Design — Design philosophy where certain elements are designed to yield while others remain elastic, ensuring ductile failure modes.
- Compactness Ratio — Classification of cross-sections based on width-thickness ratios, determining whether plastic, inelastic, or elastic behavior governs.
- Composite Action — Structural interaction between steel beam and concrete slab via shear connectors, increasing strength and stiffness.
- Coped Beam — Beam with notched flange at the connection to fit against another member, requiring checks for block shear and reduced capacity.
- Ductility — Ability of a material or structure to undergo plastic deformation without fracture, essential for seismic design.
- Effective Width — Reduced width used in cold-formed steel design to account for local buckling in compression elements.
- Elastic Buckling — Theoretical buckling load based on elastic material behavior, used as the basis for column design curves.
- Fillet Weld Leg Size — The nominal dimension of each leg of a fillet weld, used with throat thickness to determine weld capacity.
- Fillet Weld Throat — The effective throat thickness of a fillet weld, equal to 0.707 × leg size for a 90° equal-leg weld.
- Gamma Factor (γM) — Partial safety factor for resistance in Eurocode design, equivalent to 1/φ in LRFD terminology.
- Groove Weld — Full or partial penetration weld in a prepared joint, capable of developing the full strength of the connected parts.
- Limit State Design (LSD) — Design philosophy checking both ultimate and serviceability limit states, used by AS 4100 and CSA S16.
- Load and Resistance Factor Design (LRFD) — Design method applying separate factors to loads and resistances, used by AISC 360.
- Neutral Axis — Line through a cross-section where bending stress is zero, separating tension and compression zones.
- Notch Toughness — Measure of steel's ability to resist brittle fracture at low temperatures, specified by Charpy V-notch testing.
- Phi Factor (φ) — Capacity reduction factor in LRFD design, accounting for material and dimensional variability.
- Plastic Moment (Mp) — Bending moment at which the entire cross-section yields, forming a plastic hinge.
- Residual Stress — Internal stresses locked in steel sections from manufacturing, affecting buckling behavior and early yielding.
- Section Classification — Categorisation of cross-sections as compact, non-compact, or slender based on local buckling potential.
- Service Load — Expected load under normal use conditions, used for deflection and serviceability checks.
- Stiffness Matrix — Mathematical representation relating nodal forces to displacements in structural analysis.
- Torsional Buckling — Buckling mode involving twisting about the longitudinal axis, critical for cruciform and thin-walled open sections.
Related Pages
- Design Guides — Step-by-step workflows and worked examples
- Design Codes Reference — AISC 360, AS 4100, EN 1993, CSA S16 coverage
- Reference Hub — Comprehensive steel design reference tables
- All Tools — Free online structural steel calculators