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previous, continuous, extra, uninterrupted, main, equal, temporary, short-term, costly, added, the same, former, expensive, principal
IV. FILL IN THE MOST SUITABLE WORD.
1.The bridge over the Dnepr River carries a six-… roadway. a) linen b) line c) lane
2.The girders are made of low-alloy… .
a) stool b) steel c) still
3.Bolting was used where automatic welding was… . a) imperfect b) impractical c) impressible
4.The girders were stiffened with a temporary … system. a) stub b) street c) strut
5.THE STAY CABLES ARE … IN THE CAST-IN-PLACE
CONCRETE.
a) anchored b) angered c) annoyed
6. Concrete lends itself better to architectural … than steel. a) transshipment b) trimmer c) treatment
V. MATCH THE BEGINNINGS WITH THE ENDINGS.
1.The bridge carries…
2.The box girders are erected …
3.The steel girders were…
4.The anchor spans consist…
5.The aerodynamic stability of the bridge was investigated…
a)… by launching.
b)… a roadway, two rail tracks and four water pipes.
c)…of concrete box segments.
d)… by calculations.
e)… made of low-alloy steel.
VI. Make up questions from the words and answer them.
1.What / over / the new / the Dnepr / South Bridge / does / of / consist?
2.Stiffening / what / the / made / are / girders / of?
3.How / assembled / the / were / girders / steel?
4.What / to provide / mass / made / the necessary / was / counterweight?
5.What / the / look / does / pylon / like?
6.What / the pylon-girder / you / junction / say / can /about?
7.Was / distribution / connections / stress / verified / in?
Home Exercises
I.Memorize the words from Ex. I page 83.
II. Paraphrase the sentences using the Passive Voice.
1.High-strength bolts fixed field splices.
2.They preassembled the steel girders on the shore.
3.A temporary strut system stiffened the girders.
4.They used modified K-type concrete box segments in the approach spans.
5.The location of pylon legs is between the roadway and the rail tracks.
III. Tell everything you know about the new South Bridge over the Dnepr River in Kiev using your key words.
TEXT 21
I. Listen and repeat:
comprise |
[kqm'praIz] |
dead weight |
["ded 'weIt] |
shear connector |
['SIq |
groove |
kq'nektq] |
hollow |
[gru:v] |
|
['hOlqu] |
включать; содержать собственный вес шпонка; анкер; жесткий упор паз, канавка
полость, углубление; выемка; полый
II. Why is it necessary to strengthen bridges? Is it done often or seldom? Why? Read the text and say why the road bridge over the river Dvina in Vitebsk was strengthened.
Strengthening a road bridge over the river dvina
Some details of reconstruction of the road bridge over the river Dvina in Vitebsk are given in the November 1970 issue of “Transportnoye Stroitelstvo”. The bridge was erected in 1934. It crosses the main stream of the river in two continuous spans (2 x 63 m) comprising four steel trusses carrying a reinforced concrete deck. During the last war the bridge was partly destroyed and when reconstructed its carrying capacity was limited to 2.5 t. The bridge had to be strengthened.
First proposal for the reconstruction called for a new reinforced concrete deck and for the prestressing of the reinforced steel trusses. The proposed method was rather laborious and a new, cheaper, speedier and more elegant schemes for strengthening the river spans was put forward and found acceptable.
The design called for the composite action of the existing concrete deck with steel trusses and for the reduction in dead weight.
The execution was simple. First the wearing surface was removed from the deck. Holes were cut next in the concrete deck over panel points in trusses where steel shear connectors were riveted to the top boom to ensure interaction between the truss and the concrete deck.
The next operation was to place eight 200 t hydraulic jacks under each main truss over the central pier and to lift the superstructure 20 cm. To avoid cracking of the concrete, transverse grooves were cut in the deck slab prior to lifting. The raising of the structure resulted in the reversal of stresses in the trusses. The trusses were then reinforced according to the design requirements and in situ concrete was poured into the holes in the deck to bind it with the steel truss. Expanding cement was used in the concrete mix.
When the concrete had reached its designed strength the superstructure was lowered and the jacks removed. Calculations showed that about 50% of the working stresses in some truss components were due to the dead load only. To reduce the loading lightweight concrete was used for wearing surface and further reductions in weight were achieved by using asbestos cement pipes for hollow type deck construction.
III. Match the English and the Russian equivalents. Make up sentences with the English words and let your partner translate them.
destroy |
удалять |
reduce |
достигать |
remove |
разрушать |
strengthen |
приклепывать |
rivet |
заливать |
pour |
сокращать |
achieve |
усиливать |
IV. Fill in the appropriate word from the list below: consists, reduce, between, necessary, filled, avoid
1.The road bridge over the river Dvina in Vitebsk … of two continuous spans.
2.Reconstruction was … to strengthen the structure.
3.Steel shear connectors were used for interaction … the truss and the concrete deck.
4.Transverse grooves were cut in the deck slab to … cracking of the concrete.
5.The holes were … by concrete to bind the deck with the steel truss.
6.To … the loading lightweight concrete was used.
V. Analyse the text and determine the main and additional information of each paragraph.
VI. Retell the text. Use the answers to the following questions:
1.Why had the road bridge over the river Dvina to be strengthened?
2.What can you say about the first proposals for the reconstruction?
3.What advantages did a new scheme for strengthening the river spans have?
4.What was the first stage of the reconstruction work?
5.What was done during the next operation?
6.When was the superstructure lowered and the jacks removed?
7.What did calculations show?
8.How was the reduction of the loading achieved?
Home Exercises
I. Memorize the words from Ex. I page 86.
II.Use this model for compression:
Model: the tubes made of steel – steel tubes
The deck made of reinforced concrete; the method which was proposed; the trusses made of reinforced steel; the spans over the river; the bridge that was partly destroyed.
Text 22
I. Scan the text for 10 minutes and choose the answer which you think fits best according to the text. Then read the text carefully and check your ideas.
1. The elegant century old suspension bridge is …
a) the Blackfriars Bridge b) the Hampton Court Bridge c) the Hammersmith Bridge
2. The earliest bridge in Great Britain is …
a) the Old London Bridge b) the Tower Bridge c) the Albert Bridge
3.The Old London Bridge was of great danger for ...
a) pedestrians b) automobiles c) boats
4.The «Lockwood» is a …
a) chapel b) viaduct c) ferry 5. Over the Thames there are …
a) 26 bridges b) 16 bridges c) 23 bridges 6. The «Britannia» bridge was made of …
a) cast iron b) stone c) steel
BRIDGES OF GREAT BRITAIN
There are twenty-six bridges spanning the Thames. The most famous among them are: the Tower Bridge erected in 1884 and designed by Sir Horace Jones and Sir John Wolfe Barry, the London Bridge (its medieval predecessor, packed with shops and houses was a virtual village on the river), the Southwark Bridge, the Hungerford Bridge, the Blackfriars Bridge decorated with the finest ironwork and massive supports shaped like pulpits which recall the monks who once lived on the left bank, the Waterloo Bridge commemorating the Duke’s of Wellington victory over Napoleon, the Rail and Foot Bridge, the Westminster Bridge opened in 1750 despite protests by watermen fearing competition for their ferries, the Lanberth Bridge, the Vauxhall Bridge sporting statures representing Architecture, Agriculture and Science, the Chelsea Bridge, the Albert Bridge painted in wedding cake colours of rose and pistachio and bearing the order for troops to «break step» when marching across, the Battersea Bridge, the Wandworth Bridge, the Putney Bridge, the elegant century old suspension Hammersmith Bridge, the Chiswick Bridge, the Kew Bridge, the Twickenham Bridge, the Richmond Bridge built in 1774 and widened in 1930 being the oldest still used on the river, the Kingston Bridge and the Hampton Court Bridge. Many bridges have been renovated over the last decade, their designes highlighted with new coats of paint.
In addition to the above-mentioned passages over the Thames there is the Woolwich Ferry there.
The Old London Bridge is the earliest bridge in Great Britain having the historical evidence. Its construction began in 1176 and lasted during 33 years. The outstanding scientist in the field of bridge building Academician G. Perederey who contributed greatly to bridge design in Russia, gave the contemporary assessment of the Old London Bridge: «Twenty rather formless piers of different thickness were built at differed intervals from one another on piled grillages which were protected from the scour by the riprap. The spans were not long and some of them were bridged by arches, the other – by beams. The bridge looked as if it were a dam on the river and caused essential drop in water level, which was of great danger for boats. Chapels, shops and manystoried houses were densely built on the bridge. It was always overcrowded...»
From time to time fires broke out in those buildings on the bridge though everything and the bridge itself were made of stone. It’s interesting to note that 650 years later when modern London Bridge was being built to replace the old one, the workers found well-preserved wooden piles under water surface.
Two unique viaducts built in Great Britain in the 19-th century represent the most vivid achievements in world bridge construction. One of them is the «Mouth Water» with supports of 35.4 m high. It was built in 1822 and the other
was built in 1848. That structure was called the «Lockwood». Its supports were 36 m high and 1.36 m wide.
The stone bridge «Chester» built in 1834 is well known. Its 61 m long span was claimed as world record for a masonry bridge till 1842.
The first cast-iron bridge was also built in Great Britain in 1779 to span the Severn at Coalbrookdale. A new page was written in the history of the world bridge erection. The bridge represented a tracery cast iron arch with 30,6 m span. The spandrel was also made of thin cast-iron bar moldings.
And the most celebrated bridge «Britannia» was built in 1850. It was erected for the railway load. The bridge has survived to our days. It is a cast iron continuous box structure (in fact it is a tube). The trains travel through it. The span length strikes even our contemporary engineers – two middle spans are 140 m long each and each land span is 70 m long. The initial design for the «Britannia» bridge was made for a suspension type. The stone towers were erected with the holes for carrying chains. These towers remain as bridge decoration because the continuous beam appeared to be strong enough to carry the necessary load.
The Tower Bridge is a symbol of Great Britain. This unique structure is a combination of a modern steel bridge and a medieval masonry structure. Its towers are built according to a lift type in order to let large ships go under it. This is the only bridge in the world which combines suspension structures with a span lifted vertically with the help of pylons which support carrying chains.
II. Match the Russian and the English equivalents.
слой |
predecessor |
выдающийся |
pulpits |
проповедники |
coat |
ажурная работа |
overcrowded |
предшественник |
molding |
переполненный |
tracery |
формовка |
outstanding |
III. Fill in the missing word.
1.Many bridges in Great Britain were covered with new … of paint.
2.The Tower Bridge is a … of Great Britain.
3.A bridge across the Severn built in 1779 was a … bridge.
4.The Old London Bridge had … piers.
5.The «Britannia» bridge was built for …
6.Along the Old London Bridge there were … and houses.
IV. Look at fig. 11, 12. What bridges of Great Britain are represented there? Prove your answer.
Fig. 11
Fig. 12
V. What bridge of Great Britain is not mentioned in the list below? Can you describe it?
the Rail and Foot Bridge; the Chelsea Bridge; the Kew Bridge; the London Bridge; the Battersea Bridge; the Southwark Bridge; the Hungerford Bridge; the Blackfriars Bridge; the Westminster Bridge; the Lanberth Bridge; the «Chester» Bridge; the Vauxhall Bridge; the Albert Bridge; the Wandworth Bridge; the Putney Bridge; the Tower Bridge; the Hammersmith Bridge; the Chiswick Bridge; the Twickenham Bridge; the Waterloo Bridge; the Richmond Bridge; the Kingston Bridge; the Hampton Court Bridge; the «Britannia» Bridge
Home Exercises
I.Choose the Russian equivalent.
massive – массив, массивный, масса; troop – труп, труппа, отряд;
waterman – водяной, водолаз, лодочник; grillage – ростверк, грильяж, рашпер; cast iron – бракованный утюг, сталь, чугун
II. You are in Great Britain. Write a letter describing some places of interest. Do not forget to mention bridges you like.
Text 23
I. Read the information and say if the given footbridge can convey traffic and why.
FOOTBRIDGE AT WIESBADEN-SCHIERSTEIN HARBOUR
An interesting structure was built to commemorate the centenary of the Dyckerhoff cement plant in Germany. The footbridge was presented by the Dyckerhoff Co. to the City of Wiesbaden. Located at the entrance of the Rhine Port at Schierstein, the structure is destined to link Biebrich with Niederwailluf, situated on both shores of the river.
The footbridge was built by successive overhangs, using prestressed lightweight concrete, mostly of white colour. The bridge of the arch type; the span between the axis of abutments amounts to 96.40 m, while the rise is of 15 m. Because of heavy river traffic, the bridge was erected without scaffolding or centering, by the cantilever method. The structure was prestressed with Dywidag bars. The overall length referred to above (96.40 m) was divided into three parts: 16.10 m + 64.20 m + 16.10 m. The end parts are of heavy concrete construction, while lightweight concrete was used for central part. This central part constists of 21 voussoirs, which represent a volume of concrete only 180 m3, a rather low figure. It must be noted that high strength cement was used for the central part.
Each work, two voussoirs were concreted by the cantilever method. According to tests carried out by the Dyckerhoff Cement Co., both normal concrete and light concrete showed the same behaviour as regards shrinkage and creep.
An interesting feacher worth mentioning is the use of counterweight approach ramps, providing an original static arrangement and reducing the weight of the foundations, which in this case was a rather expensive item, because of the nature of the soil.
With its length of nearly 100 m and a light concrete zone of some 64 m, the Wiesbaden footbridge was (at the time of its erection) the longest prestressed light concrete footbridge in the world.
II. Give Russian equivalents:
prestressed lightweight concrete; axis of abutment; scaffolding; cantilever method; heavy concrete construction; high strength cement; counterweight approach ramp.
III. Find antonyms to the following words:
exit, destroy, light, low, different, cheep, in accordance with.
IV. Complete the following sentences using the text.
1.The structure is destined to…
2.The footbridge was built by…
3.The bridge was erected without…
4.The end parts are…
5.It must be noted that high strength cement…
6.Both normal concrete and light concrete…
V. Compare the English sentences with their translations. Is the Russian
version correct? |
|
1. The footbridge was presented by |
a) Пешеходный мост представлял |
the Dyckerhoff Co. |
компанию Дайкерхоф. |
2.The bridge was erected without b) Мост возводился без лесов. scaffolding.
3.It must be noted that high strength с) Нужно записать, что высоко-
cement was used for the central part. |
прочный цемент использовался для |
|
центральной части. |
4. Both normal concrete and light |
d) И нормальный и светлый бетон |
concrete showed the same behaviour. |
вели себя одинаково. |
VI. Find in the text ing-forms and define to what parts of speech they belong.
VII. Work in pairs. Put 3 questions to every paragraph of the text. Compare your questions with the questions of your partner. Answer the questions you have not got in your list.
VIII. Copy and complete the table.
bridge Wiesbaden footbridge
material
type
method of erection
lengh
IX. Describe the Footbridge at Weisbaden-Schierstein Harbour.
TEXT 24
I. Listen and repeat:
tier |
[tIq] |
ярус |
fortify |
['fO:tIfaI] |
укреплять |
vantage |
['va:ntIG] |
преимущество |
gorge |
[gO:G] |
узкое ущелье |
tortuous |
['tO:Cuqs] |
извилистый |
trim |
[trim] |
отделывать; зачищать |
spate |
[speIt] |
наводнение; паводок |
II. Read the text and say if there is a difference between bridge building in France and in Switzerland. Give arguments using sentences from the text.
FRENCH AND SWISS BRIDGES
Turning to France, in Provence we find perhaps the greatest Roman work of all, the famous aqueduct of the Pont du Card, built to carry water to the ancient city of Nemausus, now called Nimes. This is a three-tiered bridge with a total height of more than 160 feet. The lowest tier has six arches, ranging from 50 to 80 feet in span and at this level a modern road has been built alongside, on a bridge of a design, which harmonizes with the Roman work. Because of the widening of the valley the second tier has eleven arches, and as the widest arch in the first tier spans the river, so the widest arch in the second tier is immediately above it. This is the architectural centre of the structure, although not the geometrical centre. The third tier has 35 arches, and is so dimensioned that there are three arches immediately over each lower arch, but exactly four over the wider span.
It is not known who designed the Pont du Card, or when it was built. Authorities differ, but the historian M. Menard, believes it was authorized by Agrippa about the year 19 B.C. But old it certainly is, for the water channel along the top is almost blocked up with thick deposits of lime. No water runs through it today, for the watercourse is broken at both ends and the aqueduct leading to the bridge interrupted in many places; all that remains is the bridge itself. The collapse of the Roman Empire led to the Dark Ages in Europe; barbarianism took over from civilization, communications were severed and the need for bridges and the ability to build them disappeared. No more were seen for several hundred years and the earliest medieval bridge we can find is that over the River Lot at Espalion in France, whose age has been disputed for a very long time, but may be supposed to have been built by Charlemagne about the year 800. It is a bridge of crude workmanship, although strong enough, and marks the emergence of a creative art from the anarchy of barbaric Europe.
As bridges became necessary again for the movement of people, they were also points of weakness in defense, for they afforded easy passage alike to friend and foe. It became the custom to overcome this weakness, at strategic points, by constructing fortified bridges, and while only two of these are to be found in Britain, one at Warkworth in Northumberland, the other at Monmouth, there are many examples on the Continent, particularly in France and Spain. Of these, probably the finest is the Pont Valentre at Cahors in France, built in 1308. It has six arches of about 54 feet span, and although it might look more graceful with