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I Английский язык для студентов строительных специальностей
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SUPPLEMENTARY READING | 293
developments in the graphical representation of numerical data during the 1840s that increased the speed of performing engineering calculations. Charts devised by Leon Lalanne, the pioneer of this technique, showed, for example, how to represent an entire year's data for temperature and wind speeds in a single diagram. He also published charts for multiplication or division of numbers by graphical means.
Improving engineering education.
The specialist education of civil engineers grew out of various schools of military engineering in continental Europe, especially in France, in the late seventeenth and early eighteenth centuries. The first school of engineering open to the public was in Prague, now in the Czech Republic, in 1707 — a school that proudly celebrates its history back to 1344, when the Prague Public Engineering and Metallurgical School was founded.
The famous Ecole des Ponts et Chaussees opened in Paris in
1747 under the directorship of the bridge engineer Jean-Rodolphe
Perronet. The Ecole des Mines followed in 1783 and the first of
many ecoles d'arts et metiers, which were rather less academic than
the Ecole des Ponls et Chaussees, though hardly less prestigious,
opened in 1780. The Ecole Centrale des Arts et Manufactures was
formed in 1829. Other schools were opened to address the technical
needs of craftsmen too, for instance the Ecole Royale Gratuite de
Dessin — the Royal Free School of Drawing — which was founded
in 1766.
The idea of polytechnical education, dedicated to harmonising theory and practice, spread through continental Europe with remarkable speed. Seven polytechnic schools were formed in Germany in the first 30 years of the nineteenth century. In Austria schools were formed in Prague (1806), Vienna (1815) and Cracow (1833). There were no similar schools in Britain during this period. The establishments that served anything like the role of the continental polytechnics were a number of military academies that trained engineers for the army and navy, the most famous of which was the Royal Military Academy at Woolwich in east London, established in 1741.
Edinburgh University was the first to offer lectures on applied mechanics in the 1790s, but such a course was not intended as part of a programme to produce academically trained engineers. Engineers in Britain were largely self-educated in their spare time until the mid-nineteenth century.
Publishing books and periodicals.
The first comprehensive books on civil engineering, which also served many of the needs of military engineers, were by the military engineer Bernard Forest de Belidor (1697-1761). His first, published in 1729, was "La Science des Ingenieurs". Despite its title, however, it contained relatively little engineering science as we know it (science meant body of knowledge).
Belidor's second book, "Architecture Hydraulique" (1737— 1753), in four volumes, was radically different. Its style and mathematical rigour followed that of a scientific text book. These books were followed by many more written by the engineers who gave courses at the growing number of polytechnics in continental Europe.
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Both Smeaton and Telford had copies of Belidor's "Architecture Hydraulique" in their libraries and Telford owned many more of the French classic engineering texts published in his lifetime, including the encyclopaedic "Art of Building" by Jean Rondelet (1805-1810) and books describing bridge projects by Perronet (1788) and Wiebeking (1810) at a time when there was nothing equivalent in English. He also owned several German books — six by Jacob Leupold, dating from the 1720s and a book on hydraulic engineering by Wiebeking (1811-1813). Of the books in English in the libraries of Smeaton and Telford, the great majority were on mathematics and physics.
While a number of scientific academies, especially in France, published papers of interest and relevance to engineers during the eighteenth century, the papers of the Ecole Nationale des Ponts et Chausees were the first entirely devoted to civil engineering. The first periodical, published with the intention of keeping professional engineers informed of developments, was produced in 1797 by Johann Eytelwein (1764-1849), an engineer in Berlin's building department.
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SUPPLEMENTARY READING 295
Conclusion.
For the whole of the eighteenth century and well into the nineteenth century, France led the world in terms of developing engineering science and trying to use it in engineering design. Nevetheless, Smeaton and Telford were among the world's leading engineers, and Britain saw many of the world's leading engineering projects. The marked contrast in the nature and level of engineers' education, and their approach to engineering design between Britain and continental Europe, remained well into the twentieth century. (New Civil Engineer International, May, 2008)
^ТЕХТЗ
WINDY CITY WONDER by Jessica Rowson
Clever engineering has meant that North America's tallest
residential building will be solid as a rock despite its windy location.
Nestled among the forest of skyscrapers on the Chicago skyline,
the 92 storey Trump Tower is currently notching its way up to
become the city's second tallest building. The 415 m tower will be
completed in January 2009. The stepped concrete building has been
designed to reflect the height of nearby buildings by architect and
engineer for the project Skidmore, Owings & Merrill (SOM).
The first step aligns with the 130 m high Wrigley Building, the
second the 179 m high Marina City Towers, and the third the 212 m
high IBM Plaza, known as 330 North Wabash.
As important as these steps — also known as setbacks — are architecturally, they also have an important engineering role as they each contain an outrigger stability system. These 5.3 m deep by 1.7 m wide concrete monoliths transfer lateral loads between the perimeter columns and the central core. SOM associate partner Robert Sinn explains that the lateral shear resistance of the core and overturning resistance of the perimeter structure are mobilised by linking them at discrete levels using outrigger trusses or beams. He adds that this means just a few heavier vertical elements are
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needed on the perimeter to keep the building stable, freeing up the facade.
The outrigger beams take up a storey height and are heavily reinforced. In some areas conventional bars are even replaced by an equivalent area of steel plate to ease congestion. Contractor Bovis Lend Lease is using self compacting concrete to penetrate densely reinforced areas. Surprisingly, the tall building does not require dampers to limit its movement. This is because of the stabilising effect of the heavy concrete core and columns and the setbacks. The asymmetric setbacks change the cross section of the building, so changing the frequency of wind passing it. This means that vortices, which would cause the building to move more, cannot build up.
Any massive building needs massive foundations. The building sits on 30 m long piles founded on bedrock. A permanent steel liner, which seals the excavation, cuts through 18 m of stiff clay and 12 m of boulders and fractured rock to form a socket in solid rock. On completion the Tramp Tower will hold the record for the world's highest residential building, but only for a year. After that it will be dwarfed by the 610 m, 150 storey Chicago Spire. Finite element analysis.
Engineers had to deal with the inherent problem of the uneven load distribution of a massive, asymmetrical building and its tendency to move sideways under its own weight. The solution was to carry out a time-based finite element analysis on the structure so that movements could be predicted and compensated for during construction. Bovis Lend Lease used these results to make millimetre adjustments at every storey to bring the building back to plumb.
Non-linear analysis predicted the short and long term displacement of Chicago's Trump Tower, which included the effects of creep and shrinkage. If no horizontal correction had been made during construction, the roof could have moved 300 mm out of line due to the combined effects of gravity, creep and shrinkage. Foundations.
A 3 m deep piled raft was poured continuously over a period of 22 hours. The concrete was poured using conveyor belts so that very few vibrators were needed; the temperature had to be carefully
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