A bridge is a structure built to span physical obstacles such
as rivers, valley, or road, for the purpose of providing
passage over the obstacle.
The first bridges were made by nature itself .
The first bridges made by humans were probably spans of
cut wooden logs or planks and eventually stones, using a
simple support and crossbeam arrangement.
TYPES OF BRIDGES
Bridges can be categorized in several different ways.
Common categories include the type of structural elements
used, by what they carry, whether they are fixed or
movable, and by the materials used.
Are horizontal beams supported at each end by
substructure units and can be either simply
supported when the beams only connect across a single
span, or continuous when the beams are connected
across two or more spans. When there are multiple spans,
the intermediate supports are known aspiers.
Is a bridge whose load-bearing superstructure is
composed of a truss. This truss is a structure of
connected elements forming triangular units.
Are built using cantilevers—horizontal beams
supported on only one end. Most cantilever bridges
use a pair of continuous spans that extend from
opposite sides of the supporting piers to meet at the
center of the obstacle the bridge crosses.
Are suspended from cables. The earliest suspension
bridges were made of ropes or vines covered with pieces
of bamboo. In modern bridges, the cables hang from
towers that are attached to caissons or cofferdams.
The Great Belt Bridge
Is actually two bridges – an Eastern and a Western section, split by the
small island of FionaThe East Bridge, a 1,624 meter (5,328 feet) long
suspension bridge crosses the deepest part of Storebælt between the
island of Zealand and Fiona
Was completed in 1883, connects Manhattan and Brooklyn by spanning
the East River. At the time it opened, and for several years, it was the
longest suspension bridge in the world and it has become a famous and
iconic landmark of New York.
Is the world’s fourth longest cable stayed bridge. This is also the first girder
bridge of Shanghai with a structural composition of steel and concrete. Before
the year 1991, people used to communicate between Puxi and Pudong with
the help of the ferry service. After the construction of the bridge completed in
the year 1991, it connected Puxi to Pudong.
Sydney Harbour Bridge
Is one of Australia’s most well known and photographed landmarks. It is
the world’s largest (but not the longest) steel arch bridge with the top of
the bridge standing 134 meters (440 feet) above Sydney Harbour.
Also known as the Pearl Bridge, is the longest suspension bridge at
1,991 meters in the world. It spans the Akashi Strait in Japan
connecting Kobe on the mainland and Iwaya on Awayi Island.
The Millau Bridget
Is an enormous cable-stayed road-bridge that spans the valley of the
river Tarn near Millau in southern France. It is the tallest vehicular
bridge in the world, with the highest pylon’s summit at 343 meters
(1,125 ft) — slightly taller than the Eiffel Tower.
The Golden Gate Bridge
Is a suspension bridge spanning the Golden Gate, the strait between San
Francisco and Marin County to the north. The masterwork of architect
Joseph B. Strauss, whose statue graces the southern observation deck, the
bridge took seven years to build, and was completed in 1937.
Is a combined bascule and suspension bridge in London, over the River
Thames. It is close to the Tower of London, which gives it its name and
has become an iconic symbol of London. Construction started in 1886 and
took eight years to build. The bridge consists of two towers which are tied
together at the upper level by means of two horizontal walkways which are
designed to withstand the forces of the suspended sections of the bridge.
A smile is the bridge that put together two