Bridge
A
bridge is a structure built to span a gorge, valley, road, railroad
track, river, body of water, or any other physical obstacle. Designs
may be built higher than otherwise needed in order to allow other traffic
(particularly ship traffic) beneath.
The purpose of a bridge is to allow easier passage by providing a continuous
more uniform more easily navigable route via what would otherwise be
an uneven or impossible path for the particular kind of thing travelling
or being transported, whether people, vehicles, trains, ships, liquids
or whatever else.
History
The first bridges were spans made of wooden logs or planks and eventually
stones, using a simple support and crossbeam arrangement.
The arch was first used by the Roman Empire for bridges and aqueducts,
some of which still stand today. The Romans also had cement, which reduced
the variation of strength found in natural stone. Brick and mortar bridges
were built after the Roman era, as the technology for cement was lost
then later rediscovered.
Rope bridges, a simple type of suspension bridge, were used by the Inca
civilization in the Andes mountains of South America, just prior to
European colonization in the 1500s.
During the 18th century there were many innovations in the design of
timber bridges by Hans Ulrich, Johannes Grubenmann, and others. The
first engineering book on building bridges was written by Hubert Gautier
in 1716.
With the rise of the Industrial Revolution in the 19th century, truss
systems of wrought iron were developed for larger bridges, but iron
did not have the tensile strength to support large loads. With the advent
of steel, which has a high tensile strength, much larger bridges were
built, many using the ideas of Gustave Eiffel.
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Ponte
é uma construção que permite interligar pontos não
acessíveis separados por rios, vales, ou outros obstáculos.
As pontes são construídas para permitirem a passagem de
pessoas, veículos, comboios ou barcos sobre um obstáculo.
História
As primeiras pontes eram travessias feitas de troncos de árvores
ou pranchas e eventualmente de pedras, usando suportes muito simples e
traves mestras.
Os arcos foram usados pela primeira vez no Império Romano, para
a construção de pontes e aquedutos, alguns dos quais, ainda
hoje, se mantém de pé. Os romanos, foram também os
primeiros a usar o cimento, o que reduziu a variação da
força que a pedra natural oferecia. Pontes de tijolo e argamassa,
foram construídas após a era Romana, à medida que
se ia abandonando a tecnologia do cimento.
Durante o século XVIII, muitas inovações no design
de pontes de madeira foram feitas por Hans Ulrich, Johannes Grubenmann
e outros.
Com o advento da Revolução Industrial, no século
XIX, foram desenvolvidos sistemas de armações em ferro-forjado
para pontes mais largas, mas o ferro, não possuía a força
de tensão suficiente para suportar grandes cargas. Com a invenção
do aço, que tinha uma maior força de tensão, foram
construídas pontes mais largas, muitas usando as ideias de Gustave
Eiffel.
Source/Fonte:
Wikipedia |
