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1)This term is a combination of the Greek “art, craft,” with “word, speech,” meant in Greece a discourse on the arts, both fine and applied. When it first appeared in English in the 17th century, it was used to mean a discussion of the applied arts only, and gradually these “arts” themselves came to be the object of the designation. By the early 20th century, the term embraced a growing range of means, processes, and ideas in addition to tools and machines. By midcentury, this notion was defined by such phrases as “the means or activity by which man seeks to change or manipulate his environment.” Today it is the development over time of systematic techniques for making and doing things.

2)These things are designed to convey the weight of a structure to the ground underneath and around it. They may be spread (made with wide bases placed directly beneath the load-bearing beams or walls), mat (consisting of slabs, usually of reinforced concrete, which underlie the entire area of a building), or floating types.

3)It is a boxlike structure used in construction work underwater or as a foundation. It is usually rectangular or circular in plan and may be tens of metres in diameter.

VI. Underline the correct word to complete each sentence.

A box caisson, open at the top/bottom and closed at the top/bottom, is usually constructed on water/land, then launched, floated to position, and sunk onto a previously prepared foundation, leaving its upper edge under/above water level. It serves as a suitable shell for a pier, seawall, breakwater, jetty, or similar work, remaining permanently in place on the sea bottom.

An open caisson, closed/open at both the bottom and the top, is fitted with a cutting bottom edge, which facilitates sinking/floating up through soft material while excavation is carried out inside through a honeycomb of large pipes, or dredging wells. As excavating proceeds and the caisson sinks, additional sections are added to the shaft above. This process is continued until the caisson has sunk to the required width/depth. A floor, usually of concrete, is laid to provide a bottom seal. The dredging wells can then be filled with concrete to complete the structure.

Pneumatic caissons are similar/different to open caissons except that they are provided with airtight bulkheads above the cutting edge. The space between the bulkhead and cutting edge, called the working chamber, is pressurized to the extent necessary to control the inflow of soil and water; thus the excavating can be performed by workmen operating in/out of the working chamber at the bottom of the caisson.

VII. Match the verbs with the prepositions, which are used after them in the text. Choose 3 verbs and make up sentences with them.

to subdivide of

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VIII. Make up 7 special questions concerning the information about supports and footings construction technology. Answer the questions of your partner.

Home Exercises

I.Memorize the words from Ex. I page 56.

II. Here are some adjectives from the text. Try to remember the nouns with which they are used. Form the comparative and superlative forms of the adjectives where it is possible.

III. Render the following information in English. Use the words below.

Earth foundation – фундамент на естественном основании; piled foundation

–свайный фундамент; section – сечение; grillage – ростверк; hollow pile – свая-оболочка; drilled pile – буровая свая; coffer – опускной колодец; sinking

–погружение.

Всложных геологических условиях, когда прочные грунты залегают на большой глубине, применяют фундаменты глубокого заложения. Данные фундаменты разделяются на несколько типов.

- Свайные фундаменты, состоящие из свай (т.е. железобетонных элементов небольшого сечения и значительной длины) и ростверка – железобетонного элемента, объединяющего сваи.

- Фундаменты на сваях-оболочках. Их отличие от обычных свай в том, что сваи-оболочки представляют собой пустотелые цилиндры диаметром до 3,0 м и длиной до 30 м.

- Фундаменты на буровых сваях, которые отличаются от свай-оболочек только способом погружения свай.

- Опускные колодцы, представляющие собой железобетонную коробку, которая погружается до расчетной глубины.

- Кессонные фундаменты, которые отличаются от опускных колодцев тем, что работа в них ведется под давлением сжатого воздуха, чтобы оттеснить воду из кессона. Данный способ сооружения фундаментов очень

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опасен для здоровья рабочих, подвергающихся перепаду давления воздуха

ватмосфере и в кессоне.

Внастоящее время не существует геологических и гидрологических условий, в которых нельзя было бы возвести фундамент глубокого заложения, являющийся более универсальным. Современные механизмы и технологии сооружения фундаментов и опор достигли высокого уровня.

IV. You have heard that a construction company is going to build a bridge across the river you live by. Write a letter of complaint. Use the following expressions for your choice.

I am writing to complain about…; I am writing to express my strong dissatisfaction with…; I was shocked by…; I insist that you…; I trust the matter will receive your immediate attention….; this is unacceptable…; I hope this matter will be resolved….

II. Read the text and pay attention to various techniques of superstructure

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erection (while reading you may make notes for better understanding).

BRIDGE SUPERSTRUCTURE ERECTION

Erection technology depends on the span type, its dimension and material. The simplest erection technique is applied for the standard beam spans. The standard reinforced concrete beams are produced at the precast works. The length of the spans for the motor way bridges ranges between 6 and 42 m. The railway bridge spans may be up to 34.2 m long.

The first method is described as following: the beams are transported by motorway or railway to the job site where one or two cranes hoist them to the designed position. When a bridge is designed as a continuous one the builders put the ordinary beams on two supports and join them into a continuous beam.

The next method of span erection is the following: reinforced concrete continuous girders are cast on the bank and then the prefabricated segments are installed by the incremental launching to the designed position. While being pushed the girder works as a cantilever resisting the dead weight. As reinforced concrete has a high density the builders use a false nose to reduce the bending moments in the girder. This method is used to construct very long span bridge. The technique has its disadvantages, which clearly limit its area of use: the concrete has to be prestressed before and it needs time to reach certain age.

Two erection methods are used for framed suspended bridges, framed overbridges and trestle bridges. The first one represents the built out concreting of a span in the sliding formwork. This structure is considered to be a monolithic one.

The next erection method represents the balanced cantilevering of framed structures from ready-made reinforced concrete segments produced at the precast works. The segments are stuck together with epoxy resin or with cement. The reinforcement free length is welded. This method of construction leaves no possibility for later correction; the elements must be fixed exactly in the right position.

The most complicated erection technology is employed for arch bridges. The classical method demands temporary piers and centering to reproduce the shape of the arch superstructure to-be constructed. The precast reinforced concrete blocks are placed on centering. The monolithic concrete arch is erected in the curvilinear formwork.

The erection of arches afloat is a much more advances technique. The arches and semi-arches are assembled on the bank and launched by the building ways to the barge, which carries these structures to the location.

III. Replace the underlined words in each sentence with one word that has the same meaning.

1. Erection technology depends on the type of a distance between the supports.

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2.As reinforced concrete has a high relation of weight to volume the builders use a false nose to reduce the bending moments in the girder.

3.While constructing very long span bridge, the segments are stuck together with a grey powder, made by burning clay and lime that sets hard after mixing with water.

4.The erection of arches floating in water is a much more advances technique.

IV. Match the similar words/word combinations:

V. What process from the given below is described?

1.Bridge construction

2.Erection of metal spans

3.Assembling of trusses

For this process standard girders or unified lattice trusses are used. The length of a standard girder is 55 m and of a unified lattice truss varies between 33 and 132 m. Metal beams are lighter than those made of reinforced concrete that is why they may be mounted by one or two cranes. When a girder is 55 m long it is cut into four blocks to facilitate its delivering to the site. A temporary pier is specially erected in the middle of the span. While erecting these blocks are placed by cranes on centering and supports. The blocks are joined by the high strength bolts.

VI. Think of a span erection method, describe it to your partner using the text and let him guess.

VII. Fill in the gaps with the words given below.

foundations; arch; support; falsework; superstructure; cables; cranes; self-supporting; welded; beam.

All bridges need to be secure at the _____ and abutments. In the case of a typical overpass _____ bridge with one support in the middle, construction begins with the casting of concrete footings for the pier and abutments. Where the soil is especially weak, wooden or steel piles are driven to _____ the footings. After the concrete piers and abutments have hardened sufficiently, the erection of a concrete or steel _____ begins. Steel beams are generally made in a factory,

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shipped to the site, and set in place by _____. For short spans, steel beams are usually formed as a single unit. At the site, they are placed parallel to each other, with temporary forms between them so that a concrete deck can be cast on top. The beams usually have metal pieces _____ on their top flanges, around which the concrete is poured. These pieces provide a connection between beam and slab, thus producing a composite structure.

Arches for _____ bridges are normally fabricated on-site. After the building of abutments (and piers, if the bridge is multiarch), a _____ is constructed. For a concrete arch, metal or wooden falsework and forms hold the cast concrete and are later removed. For steel arches, a cantilevering method is standard. Each side of an arch is built out toward the other, supported by temporary _____ above or by falsework below until the ends meet. At this point the arch becomes _____, and the cables or falsework are removed.

VIII. What assembling methods are shown in the pictures below (fig. 7 – 9)? assembling of long arches

assembling of aches on falsework assembling of discontinuous beams

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II. You are going to read the text about Moscow bridges. What would you like to know about them? Write down at least five questions which you hope the text will answer.

III. Now read the text.

MOSCOW BRIDGES

It was from the Kremlin, the first class fortress that Moscow originated. The Kremlin dates back to the 12-th century and was built upon the confluence of the Neglinnaya and the Moskva rivers, which protected the two fortress sides against enemy raids.

The Kremlin is a triangular shape in plan. So a wide and deep moat was excavated for the fortress protection from the third approach to it. And the early Moscow bridges were built to span the moat. One of those bridges at Spassky tower was a timber bascule bridge. There was another bridge that spanned the Neglinnaya River at Troitsky tower. It was called the Troitsky Bridge. It has survived to our days though it is situated in a dry place now. We can see this bridge in the middle of Alexandrovsky Garden. The matter is that the Neglinnaya River was enclosed in conduits and driven underground.

Moscow was growing and in the 16-th century the idea of spanning the Moskva by the permanent bridge captured the minds. At those days the only crossing over the river from the Kremlin to Zamoskvorechye was made of tied logs. It was a floating bridge.

In 1643 Yan Cristler was invited to Moscow. He became the designer of the first arch bridge across the Moskva. It was the Big Stone Bridge (Bolshoy Kamenny Most) with seven spans resting on stone arches. Arch spans as described in historical records were 40 arshines or 28 m long. But if it had been so the total bridge length would have been 250 m long. It seems very doubtful because the river width is considerably less. Evidently only one of the spans could

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be 28 m long and the rest of them were shorter. The old bridge was replaced in 1859. It was a three span cast iron bridge but the Moscovites were fond of its old name. Its main span was 63 m long and the length of the side spans was 36 m each. The roadway width was 16 m.

The modern Big Stone Bridge is not made of stone. It is a steel bridge with an attractive cast iron railing built in 1938 by engineer N. Kalmykov. It was erected under the Moscow Master Development Plan launched in 1932. The old bridges could not meet the requirements of the day and eleven bridges across the Moskva were built within an unprecedentedly short period. It took the builders only three years to erect them.

The modern Big Stone Bridge has three arch spans made of a highly reliable low alloy steel. The main span length is 105 m and its width is 40 m. The bridge can carry about 8 000 vehicles, 10 000 pedestrians and 120 trams per hour. A breathtaking view of the magnificent Kremlin ensemble situated on the slope of a gentle hill opens from the Big Stone Bridge spanning the Moskva River.

The Lefortovsky Bridge built in 1770 also belongs to the oldest bridge crossings across the Moskva River.

Altogehter, Moscow has about 200 bridges, most built since revolution. None of the 38 bridges across the Moskva River are alike. The Krymsky Bridge is the only suspension bridge across the Moskva River. Even though it is light and resembles openwork, it is six-lane structure. The bridge in Strogino is assembled of large ferroconcrete sections. The Moskvoretsky Bridge is a rather stark-looking bridge, whose monumental shape conforms well to the solid walls and towers of the Kremlin. It is the only bridge among the eleven bridges, which was erected of reinforced concrete and faced with pink granite. The bridge is supported by a gently sloping arch. Its main span is 95 m long. Built in 1936 – 1937 by engineer V. Kirilov to replace the old narrow bridge, it leads from Red Square to Zamoskvorechye, the district on the other bank of the Moskva. At present it is a foot-bridge as Red Square is not allowed for the city traffic.

The beautiful silvery Krymsky Bridge is the only suspension bridge across the Moskva supported by two steel chains flung across the tall pylons. Its main span is the longest over the Moskva. It is 168 m long. The wide road way accommodates six traffic lanes. The bridge was built in 1938 by engineer B. Konstantinov and architect V. Vlasov. Professor K. Yakobson who headed the «Bridges and Tunnels» department at the Novosibirsk Railway Engineering Institute during twenty-five years and was the dean of the «Bridges and Tunnels» Faculty took part in the design and construction of this bridge.

Many of Moscow bridges remember the glorious victories of Russian people and were even erected to commemorate those victories. The Borodinsky Bridge was constructed in 1912 to be a memorial of our victory over Napoleon’s troops. It is the only old bridge in Moscow preserving its original form.

Have you found the answers?

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