A bridge substructure element at the end of a span that supports the superstructure, retains the approach embankment and transfers loads to the foundation.

An assembly that transfers tensile, shear or moment forces from a structural member, connection or tendon into concrete, masonry, steel or the ground.

A protective system installed along a road, bridge or work area to restrain vehicles or pedestrians and reduce the consequences of leaving the intended path.

A steel plate fixed at the base of a column or structural member to distribute axial loads, moments and shear into the supporting concrete or foundation through bearing and anchorage.

A structural member, usually horizontal or inclined, that primarily resists loads transverse to its longitudinal axis through bending and shear.

A headed threaded fastener used with a nut, and sometimes washers, to clamp and transfer forces between connected structural parts.

A structural joint in which forces are transferred between connected parts through bolts, typically by bearing, shear, tension or slip-resistant friction mechanisms.

Members or systems provided to resist lateral loads, control sway, reduce the effective length of compression members, and stabilise the structural frame during construction and in service.

A projecting support component that transfers a supported load into a column, wall, beam or other structural member.

A structure that carries a road, railway, pedestrian route or utility across an obstacle such as water, terrain or another transport corridor.

The structural platform of a bridge that supports traffic, pedestrians or railway loads and transfers these actions to the supporting girders, trusses, arches, bearings or substructure.

A stability failure in which a compressed member or plate undergoes sudden lateral deformation before the material reaches its full compressive strength.

The zone of a building that typically contains lifts, stairs, risers and services, and may also act as a primary lateral-load-resisting element when formed by reinforced concrete walls, steel bracing or other structural systems.

The physical separator between conditioned indoor spaces and the external environment, including walls, roofs, floors, windows, doors, cladding, insulation, air barriers and waterproofing systems.

A large foundation unit or watertight chamber sunk or constructed below ground or water level to transfer structural loads to competent strata.

A structural member or system fixed or restrained at one end and extending beyond its support to carry loads without an external support at the free end.

A circular hollow steel section used as a structural member, valued for uniform properties about all axes, torsional resistance and efficiency in compression.

A loss of structural load-carrying capacity that causes part or all of a structure to fail or undergo uncontrolled deformation.

A primarily vertical structural member designed mainly to carry axial compression, often with bending, and transfer loads from floors, roofs or beams to lower structural elements or foundations.

A beam in which a steel section and a concrete slab are mechanically connected, usually by shear connectors, so they share bending resistance and act together under floor or bridge loads.

A compression member combining structural steel and concrete, such as an encased steel section or concrete-filled steel tube, designed so both materials contribute to load resistance, stiffness and fire performance.

A form of construction in which two or more materials, commonly structural steel and concrete, are connected so they act together as a single load-resisting system with combined stiffness, strength and stability.

Profiled steel decking designed to act compositely with cast-in-place concrete, using embossments or mechanical interlock to form a reinforced composite floor slab.

A composite member formed by filling a circular, square or rectangular steel tube with concrete, where the steel tube provides confinement and tensile resistance and the concrete contributes compressive strength and stiffness.

The engineered joint or assembly that transfers forces between structural members, components or supports, using bolts, welds, plates, anchors or other connection devices.

The deterioration of a metal through chemical or electrochemical reaction with its environment, potentially reducing section size and structural capacity.

Measures that reduce or prevent deterioration of steel caused by corrosion, including protective coatings, galvanizing, material selection, detailing that avoids water traps and planned inspection and maintenance.

A mechanical device that joins two bars, rods, pipes or structural components so force or movement can be transferred between them.

A barrier constructed across a watercourse or valley to retain, control or divert water for supply, flood management, hydropower or other purposes.

The displacement of a structural member or system from its original position under load, temperature change, support movement or other action.

A construction method using accessible, reversible or replaceable connections so a structure can be dismantled into usable components rather than demolished as waste.

A design approach that plans connections, access, tolerances and material choices so building components can be safely separated, recovered and reused or recycled at the end of their service life.

A design strategy that enables structural members, components or assemblies to retain sufficient integrity, identification and demountability for future use in another structure or location.

The capacity of a material, member or connection to undergo significant plastic deformation before fracture, allowing redistribution of forces and warning before failure.

The ability of a structure, material or component to resist deterioration and continue satisfying strength, serviceability and functional requirements over its intended service life with appropriate maintenance.

A raised earth or rock structure built to support a road, railway or other infrastructure at the required level above the surrounding ground.

The on-site positioning, aligning, connecting and temporary stabilising of prefabricated structural members to form the permanent structural frame or system.

The controlled workshop process of cutting, drilling, welding, bolting, forming, coating and assembling steel components before they are transported to site for erection.

The external face or elevation of a building, including cladding, glazing, support framing, joints and interfaces that contribute to appearance, weather protection and environmental performance.

Measures used to maintain structural performance for the required fire resistance period, including applied protection, boards, intumescent coatings, concrete encasement, fire-resistant detailing or performance-based fire design.

The projecting part of a structural section, such as an I-section, that contributes strongly to bending resistance by carrying axial tension or compression.

The horizontal plan area of a building level, often referring to the usable or lettable area available for occupancy, circulation, services and structural layout on that floor.

A bridge designed primarily to carry pedestrians, and sometimes cyclists or maintenance vehicles, across a road, railway, watercourse, valley or other obstacle.

A temporary or permanent mould and support system used to shape and contain fresh concrete until it gains sufficient strength to support itself.

The lowest load-transfer part of a structure, such as footings, rafts, piles or pile caps, designed to safely transmit structural loads to the ground without excessive settlement or bearing failure.

The separation or cracking of a material when stress and crack growth exceed its capacity to resist failure.

Steel coated with a layer of zinc, commonly by hot-dip galvanizing, to provide sacrificial corrosion protection and extend durability in suitable exposure conditions.

A principal beam that supports other beams, floor elements or bridge deck components and transfers their loads to columns, piers or bearings.

A principal public road designed and managed for the movement of vehicles between settlements, regions or major destinations.

Hollow steel tubes with circular, square or rectangular profiles used structurally.

A construction system that intentionally combines different structural materials, such as steel, concrete and timber, so each material is used where its mechanical, durability or constructability advantages are most effective.

The physical systems and assets that support economic and social activity, including transport networks, bridges, railways, ports, utilities, energy facilities, water systems and industrial structures.

A structural system designed to span a relatively large distance between supports without intermediate columns or supports, commonly using trusses, arches, space frames, cable systems or deep beams.

A form of off-site construction using factory-produced three-dimensional units that are transported to site and connected to form part or all of a building or structure.

A construction approach in which components, panels, modules or assemblies are produced away from the project site and then delivered for lifting, fixing and integration into the permanent works.

An intermediate vertical support that transfers bridge superstructure loads to the foundation between the end supports.

A slender deep-foundation element driven, bored or installed into the ground to transfer loads through end bearing, shaft resistance or both.

The manufacture or assembly of building or infrastructure elements away from their final location, under controlled conditions, before transportation and installation on site.

A rolled steel track component that guides and supports railway vehicle wheels and transfers wheel loads to sleepers and the track structure.

An infrastructure system of tracks, earthworks, structures, stations and associated equipment used for guided rail transport.

Deformed or plain steel reinforcing bar embedded in concrete to carry tensile forces and develop composite action with the surrounding concrete.

A rectangular hollow steel section used as a structural member where directional bending stiffness, torsional resistance or clean exposed profiles are required.

Steel bars, mesh, fibres or other embedded elements provided in concrete to resist tensile forces, control cracking and improve structural performance.

A permanent mechanical fastener formed by upsetting a metal shank through aligned holes to clamp connected parts together.

A prepared transport route comprising pavement, earthworks, drainage and associated structures for vehicle and other surface traffic.

The ability of a structure to tolerate local damage, accidental actions or member loss without developing disproportionate or progressive collapse.

Profiled steel sheets used to span between roof supports and carry roofing, insulation, imposed loads, wind actions and construction loads to the supporting structure.

The ability of a structure or infrastructure system to resist, absorb, adapt to and recover from earthquake effects while limiting collapse risk, damage, downtime and loss of function.

The period during which a structure, component or material is expected to meet specified performance requirements under defined use, exposure and maintenance conditions.

A device, such as a headed stud, bolt, channel or dowel, used at the steel-concrete interface to transfer longitudinal shear, limit slip and enable composite action.

A broad, relatively thin structural element, usually horizontal, that carries distributed loads and transfers them to beams, walls, columns or foundations.

The distance between adjacent points of support of a structural member or system, usually measured centre-to-centre of supports unless otherwise stated.

A connection that joins two lengths of a structural member so forces are transferred across the discontinuity.

A square hollow steel section used as a structural member, commonly for columns, bracing, trusses and exposed architectural steelwork.

The ability of a member or structural system to maintain equilibrium and resist buckling, overturning, sliding or other unstable behaviour.

Profiled steel sheets used as permanent formwork, floor decking or roof decking, and in some cases as part of a composite slab system.

A flat rolled steel product of specified thickness and grade used to fabricate structural members, connection plates, base plates, stiffeners, gussets and other construction components.

A building in which the main load-resisting frame, typically beams, columns, bracing and connections, is predominantly made of structural steel.

A plate or section attached to a structural member to restrain local deformation, prevent buckling or distribute concentrated forces.

The resistance of a material, member or structure to deformation under an applied load or action.

The deformation of a material expressed as a change in length or shape relative to its original dimension.

A measure of material or member efficiency, expressed as strength relative to self-weight or density, used when assessing lightweight structural solutions.

The internal force intensity developed within a material, commonly expressed as force per unit area.

An assembly of beams, columns, bracing, connections and other members that supports and transfers gravity and lateral loads to the foundations.

The condition of a structure being able to sustain required loads and actions with adequate strength, stability and serviceability, without unacceptable deformation, damage or collapse.

The capacity of a structure to prepare for, withstand, adapt to and recover from disruptive events such as earthquakes, fire, impact, flood or blast while preserving life safety and restoring function.

Steel products, such as rolled sections, plates, hollow sections and built-up members, manufactured and specified for use as load-bearing members in buildings, bridges and other civil engineering works.

Downward movement of the ground that can cause settlement, distortion or damage to foundations and the structures they support.

The portion of a building or civil structure below the superstructure that supports it and transfers its loads to the foundations and ground.

The ability of a material to absorb energy and undergo deformation before fracturing.

A triangulated framework of straight members connected at joints, designed so members carry mainly axial tension or compression to span loads efficiently.

An enclosed underground or underwater passage constructed for transport, utilities, water conveyance or access.

A long bridge formed by a series of spans that carries a road or railway across a valley, floodplain or developed area.

Oscillatory motion of a structure or component caused by dynamic actions such as machinery, traffic, wind or human movement.

A structural steel formulated to develop a stable protective oxide layer under suitable exposure conditions, reducing the need for applied coatings.

The central plate or portion of a beam or girder that connects the flanges and primarily resists shear.

A fused joint or deposited weld metal that connects steel parts and transfers forces between them.

The ability of a material to be welded under specified fabrication conditions while producing a joint that meets the required integrity and performance.

A structural joint in which connected steel parts are fused by welding so that forces are transferred through weld metal and the adjoining base material.

A waterfront structure where vessels berth for loading, unloading or passenger access, typically supported by piles or a retaining structure.