Steel Bridge Design.
Expert-defined terms from the Postgraduate Certificate in Structural Steel Design course at LearnUNI. Free to read, free to share, paired with a globally recognised certification pathway.
**AASHTO** #
The American Association of State Highway and Transportation Officials, which develops standards and guidelines for transportation infrastructure, including steel bridges.
**ABC (Accelerated Bridge Construction)** #
A construction method that uses innovative planning, design, and construction techniques to reduce the on-site construction time of bridge projects.
**AASHTO LRFD (Load and Resistance Factor Design)** #
A standard for the design of bridges that uses load and resistance factors to account for uncertainty in loads and material properties.
**Bearing** #
A device used to support and transfer loads from the bridge superstructure to the substructure.
**Bent** #
A vertical or near-vertical column that supports the bridge superstructure and transfers loads to the foundation.
**Bridge Deck** #
The horizontal surface of the bridge that supports the traffic.
**Camber** #
The intentional upward curvature of a bridge deck or beam to counteract the effects of dead load deflection.
**Cantilever** #
A structural member that projects beyond its support, such as the ends of a bridge deck or beam.
**Composite Beam** #
A beam made of two or more different materials, such as steel and concrete, that act together to resist loads.
**Connections** #
The elements that join steel members together, such as bolts, welds, or rivets.
**Continuous Beam** #
A beam that spans over multiple supports, allowing for more efficient use of materials.
**Diaphragm** #
A horizontal or vertical bracing element used to stiffen and stabilize a steel frame.
**Fatigue** #
The progressive and permanent structural damage that occurs when a material is subjected to repeated loading.
**Fracture Critical Member (FCM)** #
A steel member whose failure could cause the collapse of the entire bridge.
**Fracture Toughness** #
A material's ability to resist fracture when subjected to high stresses.
**Gerber Beam** #
A type of continuous beam that uses a series of vertical web stiffeners to resist torsional forces.
**Haunch** #
The portion of a beam or girder that is thicker than the rest of the member to resist higher bending moments.
**High #
Performance Steel (HPS)**: A type of steel with enhanced properties, such as increased strength, toughness, and corrosion resistance.
**Hinge** #
A point in a bridge where rotation is allowed, such as at the connection between two beams or girders.
**Live Load** #
The load imposed on a bridge by moving vehicles, pedestrians, or other dynamic forces.
**Moment Connection** #
A connection that allows for the transfer of moments between steel members.
**Parker Rolling Lift Bridge** #
A type of lift bridge that uses a rolling mechanism to raise and lower the bridge deck.
**Pile Foundation** #
A type of foundation that uses deep piles driven into the ground to support the bridge substructure.
**Plate Girder** #
A type of beam made of steel plates, used for long spans and heavy loads.
**Pony Truss** #
A type of truss bridge that has a single plane of triangular members supporting the bridge deck.
**Rolled Beam** #
A beam that is formed by rolling a steel plate into a curved shape.
**Simple Beam** #
A beam that is supported at two ends, allowing for the transfer of vertical loads only.
**Stay #
in-Place Forms**: Formwork used for casting concrete that remains in place after the concrete has cured.
**Stiffener** #
A thin piece of steel added to a beam or girder to increase its stiffness and resistance to buckling.
**Strut #
and-Tie Model**: A method of analyzing and designing a concrete structure by modeling it as a system of tension and compression members.
**Superstructure** #
The part of a bridge that supports the bridge deck and traffic.
**Tension Member** #
A member in a bridge that is subjected to tensile forces.
**Through Girder** #
A type of beam that is supported at three or more points, allowing for the transfer of vertical and horizontal loads.
**Torsion** #
The twisting force that is applied to a member, causing it to rotate.
**Truss** #
A structural framework made of triangular members, used for supporting bridges, buildings, and other structures.
**Ultimate Limit State (ULS)** #
The point at which a bridge fails or becomes unsafe for use.
**Vierendeel Girder** #
A type of girder that uses rectangular instead of triangular members, allowing for greater flexibility in the placement of openings and connections.
**Web Stiffener** #
A thin piece of steel added to a beam or girder to increase its stiffness and resistance to buckling.
**Welded Connection** #
A connection that uses welding to join steel members together.
**Yield Strength** #
The amount of stress that a material can withstand before it starts to deform permanently.