the second moment of area, allowing
in the structure.
Gustave Eiffel and Maurice Koechlin,
engineers for the first time to both
Steel construction was first made
demonstrating the potential of
understand structural behavior and
possible in the 1850s when Henry
construction using iron, despite the
structural materials.
Bessemer developed the Bessemer
fact that steel construction was
Towards the end of the 19th century,
process to produce steel. He gained
already being used elsewhere.
in 1873, Carlo Alberto Castigliano
patents for the process in 1855 and
During the late 19th century, Russian
presented his dissertation "Intorno ai
1856 and successfully completed the
structural engineer Vladimir Shukhov
sistemi elastici", which contains his
conversion of cast iron into cast steel
developed analysis methods for
theorem for computing displacement
in 1858. Eventually mild steel would
tensile structures, thin-shell struc-
as partial derivative of the strain
replace both wrought iron and cast
tures, lattice shell structures and new
energy.
iron as the preferred metal for
structural geometries such as
In 1824, Portland cement was
construction.
hyperboloid structures. Pipeline trans-
patented by the engineer Joseph
During the late 19th century, great
port was pioneered by Vladimir
Aspdin as "a superior cement resem-
advancements were made in the use
Shukhov and the Branobel Company
bling Portland Stone", British Patent
of cast iron, gradually replacing
in the late 19th century.
no. 5022. Although different forms of
wrought iron as a material of choice.
Again taking reinforced concrete
cement already existed (Pozzolanic
Ditherington Flax Mill in Shrewsbury,
design forwards, from 1892 onwards
cement was used by the Romans as
designed by Charles Bage, was the
François Hennebique's firm used his
early as 100 B.C. and even earlier by
first building in the world with an inte-
patented reinforced concrete system
the ancient Greek and Chinese civili-
rior iron frame. It was built in 1797. In
to build thousands of structures
zations) and were in common usage in
1792 William Struttad attempted to
throughout Europe. Thaddeus Hyatt in
Europe from the 1750s, the discovery
build a fireproof mill at Belper in Derby
the US and Wayss & Freitag in
made by Aspdin used commonly
(Belper West Mill), using cast iron
Germany also patented systems.The
available, cheap materials, making
columns and timber beams within the
firm AG für Monierbauten constructed
concrete construction an economical
depths of brick arches that formed the
200 reinforced concrete bridges in
possibility.
floors. The exposed beam soffits were
Germany between 1890 and 1897
Developments in concrete continued
protected against fire by plaster. This
The great pioneering uses of rein-
with the construction in 1848 of a
mill at Belper was the world's first
forced concrete however came during
rowing boat built of ferrocement - the
attempt to construct fireproof build-
the first third of the 20th century, with
forerunner of modern reinforced
ings, and is the first example of fire
Robert Maillart and others furthering
concrete - byJoseph-Louis Lambot.
engineering. This was later improved
of the understanding of its behavior.
He patented his system of mesh rein-
upon with the construction of Belper
Maillart noticed that many concrete
forcement and concrete in 1855, one
North Mill, a collaboration between
bridge structures were significantly
year after W.B. Wilkinson also
Strutt and Bage, which by using a full
cracked, and as a result left the
patented a similar system.This was
cast iron frame represented the
cracked areas out of his next bridge
followed in 1867 when a reinforced
world's first "fire proofed" building.
design - correctly believing that if the
concrete planting tub was patented by
The Forth Bridge was built by
concrete was cracked, it was not
Joseph Monier in Paris, using steel
Benjamin Baker, Sir John Fowler and
contributing to the strength. This
mesh reinforcement similar to that
William Arrol in 1889, using steel, after
r e s u l t e d i n t h e r e v o l u t i o n a r y
used by Lambot and Wilkinson.
the original design for the bridge by
Salginatobel Bridge design. Wilhelm
Monier took the idea forward, filing
Thomas Bouch was rejected following
Ritter formulated the truss theory for
several patents for tubs, slabs and
the collapse of his Tay Rail Bridge.
the shear design of reinforced
beams, leading eventually to the
The Forth Bridge was one of the first
concrete beams in 1899, and Emil
Monier system of reinforced struc-
major uses of steel, and a landmark in
Mörsch improved this in 1902.
tures, the first use of steel reinforce-
bridge design. Also in 1889, the
He went on to demonstrate that treat-
ment bars located in areas of tension
wrought-iron Eiffel Tower was built by
ing concrete in compression as a
22
Issue 71 December 2013
2013 71

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