TOPIC: BRIDGE TYPES
1. Introduce
A bridge is a structure built to span physical
obstacles such as a body of water, valley, or road, for
the purpose of providing passage over the obstacle.
Designs of bridges vary depending on the function of
the bridge, the nature of the terrain where the bridge
is constructed, the material used to make it and the
funds available to build it.
There are six main types of bridges: beam bridges,
truss bridges, arch bridges, cantilever bridges,
suspension bridges and cablestayed bridges.
Illustration for bridges type
I. Beam bridges
Beam bridges are the most simple of structural
forms being supported by an abutment at each
end of the deck. No moments are transferred
through the support hence their structural type
is known as simply supported.
The simplest beam bridge could be a slab of
stone, or a plank of wood laid across a stream.
Bridges designed for modern infrastructure will
usually be constructed of steel or reinforced
concrete, or a combination of both. The
concrete used can either be reinforced,
prestressed or posttensioned.
Types of construction could include having
many beams side by side with a deck across
the top of them, to a main beam either side
supporting a deck between them. The main
beams could be Ibeams, trusses, or box
girders. They could be halfthrough, or braced
across the top to create a through bridge.
Beam bridges are often only used for really
short distances because, unlike truss bridges,
they have no built in supports. The only
supports are provided by piers.
Feiyun River Bridge, Zhejiang Province
The beam bridges famous
Rio-niteroi Bridge
Seven Mile Bridge
II. Truss bridges
A truss bridge is a bridge
composed of connected
elements(typically straight)
which may be stressed from
tension, compression, or
sometimes both in response to
dynamic loads. Truss bridges
are one of the oldest types of
modern bridges. The basic
types of truss bridges shown in
this article have simple
designs which could be easily
analyzed by nineteenth and
early twentieth century
engineers. A truss bridge is
economical to construct owing
to its efficient use of materials.
The truss bridges famous
TrangTien bridge
ErieCanalRRBridge
III. Arch bridges
An arch bridge is a bridge with abutments
at each end shaped as a curved arch.
Arch bridges work by transferring the
weight of the bridge and its loads partially
into a horizontal thrust restrained by the
abutments at either side. A viaduct (a long
bridge) may be made from a series of
arches, although other more economical
structures are typically used today.
Arch bridge: construction that allows
automobiles to travel between two points
separated by an obstacle.
Portal frame: construction that carries the
weight of a suspended load to the ground.
Arch: arched vault that is supported by
the abutments.
Deck: platform of the bridge.
Lower chord: lower supporting piece.
Upper chord: upper supporting piece.
Pile: masonry pylon that serves as
support.
The arch bridges famous
Fredrikstad_BridgeacrossGlomma01 Fredrikstad Na Uy
Si-o-se Pol bridge, Iran
HarlemRiverBridges (New York , Mỹ )
Cantilever bridge
•
A cantilever bridge is
a bridge built using cantilevers,
structures that project
horizontally into space,
supported on only one end. For
small footbridges, the
cantilevers may be
simple beams; however, large
cantilever bridges designed to
handle road or rail traffic
use trusses built from structural
steel, or box girders built
from prestressed concrete. The
steel truss cantilever bridge was
a major engineering
breakthrough when first put
into practice, as it can span
distances of over 1,500 feet
(460 m), and can be more easily
constructed at difficult crossings
by virtue of using little or
no falsework.
Ironton-Russell Bridge (America)
Suspension bridge: construction that
allows automobiles to travel between two
points separated by an obstacle.
Side span: segment between two pylons
at the ends of a bridge.
Centre span: segment between two
pylons at the centre of a bridge.
Side pylon: towerlike vertical
construction situated at the side, usually
supporting the cables of a suspension
bridge or a cablestayed bridge
Foundation of a pylon: very durable
lower part of a tower.
Suspender: support cable.
Suspension cable: set of braided wire
that supports a bridge.
Pylon: towerlike vertical support that
usually supports the cables of a
suspension bridge or a cablestayed
bridge.
Stiffening girder: tightener beam
A suspension bridge is a type
of bridge which is built by
suspending the roadway from
cables attached to a master cable
which runs above the length of
the bridge. In addition to being
strong and
lightweight, suspension bridges
are also beautiful, and some of the
most famous bridges in the world
are also suspension bridges,
including San Francisco's iconic
Golden Gate Bridge and New
York's Brooklyn Bridge.
A suspension bridge is a type
of bridge in which the deck (the
loadbearing portion) is hung
below suspension cables on
vertical suspenders
This type of bridge has cables
suspended between towers, plus
vertical suspender cables that
carry the weight of the deck below,
upon which traffic crosses.
Golden gate bridge
Brooklyn Bridge
VI. Cablestayed bridges
A cablestayed bridge is a bridge that consists of one or more columns (normally referred to as
towers or pylons), with cables supporting the bridge deck.
There are two major classes of cablestayed bridges: In a harp design, the cables are made
nearly parallel by attaching them to various points on the tower(s) so that the height of
attachment of each cable on the tower is similar to the distance from the tower along the roadway
to its lower attachment. In a fan design, the cables all connect to or pass over the top of the
tower(s).
Compared to other bridge types, the cablestayed is optimal for spans longer than typically seen
in cantilever bridges, and shorter than those typically requiring a suspension bridge. This is the
range in which cantilever spans would rapidly grow heavier if they were lengthened, and in which
suspension cabling does not get more economical, were the span to be shortened.
21 tháng 5 năm 2000.
Sutong yangtze with the longest main span in the would as of 2011 1088m, side span 300m 306m high tower, total bridge length 8206m
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