Bridge Components Flashcards
COMPONENTS of a BRIDGE
- SUPERSTRUCTURE
- SUBSTRUCTURE
- FOUNDATION
Span and directly Receives the live load
Supported by bearings
deck, girders, slab above the main deck
SUPERSTRUCTURE
Support structures, located below the bearing
Transmits load to ground
piers, abutments, spandrels, caps, bearings
SUBSTRUCTURE
holds the shallow or deep base of the bridge
Footing; piles
FOUNDATION
COMPONENTS OF SUPERSTRUCTURE
- WEARING SURFACE
- DECK
- PRIMARY MEMBERS
- SECONDARY MEMBERS
- BEARINGS
OR Course
➢ Topmost layer of material
applied upon the deck to
provide smooth riding surface
and to protect deck from effects
of traffic and weathering
➢ In some instances, this is a
separate layer made of
bituminous material, while in
some it is an integral part of the
concrete deck
WEARING SURFACE
➢ The physical extension of the
roadway across the obstruction
to be bridged
➢ Component of the bridge to
which live load is directly applied
➢ Provide smooth and safe riding
surface for the traffic utilizing the
bridge and distribute loads
transversely along the bridge
cross section
DECK
TYPES OF DECK
➢ TIMBER DECKS
➢ CONCRETE DECKS
➢ STEEL DECKS
Normally referred to as decking or timber flooring
(limited to the roadway portion that receives
vehicular loads)
TIMBER DECKS
➢ Concrete permits casting in various shapes and sizes
and has provided bridge designers and builders a
variety of construction methods
➢ It is used together with reinforcement to resist
tensile stress (where concrete is weak)
CONCRETE DECKS
Composed of either
➢ Solid steel plate
➢ Steel grids
STEEL DECKS
Distributes loads longitudinally and are usually designed principally to resist flexure and shear
PRIMARY MEMBERS
BEAM TYPE primary members are
also referred to as
stringers or girders
placed between the deck slab and the top flange of
the stringer in order for the slab not to rest directly on the member
haunch
▪ Efficient for shorter spans
▪ Limited sizes and shapes
I – girders: Rolled Beams
▪ Deep girders can span very long distances
▪ Vast range of sizes and shapes
I – girders: Plate Girders
▪ Box section efficiently resists torsion effects
▪ Vast range of shape and sizes
Box Girders
➢ Are bracing between primary members
➢ designed to resist cross-sectional
deformation of the superstructure frame
➢ and help distribute part of the vertical
load between stringers
SECONDARY MEMBERS
Other secondary members (like _____________ ) composed of crossed frames at the top or bottom flanged of a stringer
➢ are used to ________________________ caused by loads acting perpendicularly to the bridge’s
longitudinal axis
lateral bracing; resist lateral deformation
TYPE OF SECONDARY MEMBERS
CROSS FRAMES
DIAPHRAMS
LATERAL BRACING
Used on steel girder bridges to provide torsional stiffness during construction and in final
condition
CROSS FRAMES
▪ Used on steel girder bridges to provide torsional stiffness during construction and in the final
condition
▪ Typically used on shallow beams
DIAPHRAMS
Used to provide lateral stiffness
and limit lateral deflections
LATERAL BRACING