Text b.

We have mentioned some problems connected with building. One of them is a foundation. Architects and engineers are aware of the problems involved in laying building's foundations. They do not always realize to what extent the earth can be pressed down by the weight of a building. Too little allowance has sometimes been made for the possibility of a heavy structure’s sinking unevenly. There are a lot of examples of foundations1 problems. One of them is the Leaning Tower of Pisa. Why did the Leaning Tower of Pisa lean? The answer is that its foundations were not soundly laid. Though the Leaning Tower is 14 feet out of the perpendicular, it has never toppled. But there is a way out. As the building began to lean over, the builders altered the design of the upper storeys to balance it. At the same time as one side of it sank into the ground, the earth beneath was compressed until it became dense enough to prevent further movement.

That's why a foundation engineer has a lot of work. But in a tall modern structure the load may be very heavy indeed. In this way the foundation engineer has an extremely important job to do. He must have understanding of soil mechanics, which entails a scientific study of the ground to see what load it can be without dangerous movement. The engineer must collect undisturbed samples of earth from various depths. By examining this, the engineer can forecast the probable shifts in the earth during and after building, according to the sort of the foundation he designs. Thus he comes to the most important decision of all in the building's construction. He decides whether the earth is a type that can best support each column on a separate solid block, or whether he must aim at lightness.

Exercise 11. Translate the words:

шов, транспортировать, опираться на, проект, пролет, труба, изгиб, грань, опорное кольцо, применять.

Exercise 12. Note in text B:

1. s- endings

2. That-functions

3. Modal verbs

Unit 9

Exercise 1. Read the following:

6/7; 365 B.C.; 816 A.D.; 1/3; 1/5; 1/2; 8/9; 0.75; 2.426; 0.6; 0.25; 3.756; 0.5; 0.25.

Exercise 2. Words to be remembered:

suspension bridge – подвесной мост

iron – железо

chain – цепь

tension – растяжение

bottom – дно, нижняя часть

freeze – замораживать

derive – заимствовать

at the turn of the century – в начале века

to be interested in – интересоваться чем-либо (кем-либо)

parabolic – параболический

rink – спортивное сооружение, каток

deck – настил

lightweight structure – легкая конструкция

dead weight – собственный вес

live weight – рабочий (временный) вес

flutter (v., n.) – вибрация, вибрировать

Exercise 3. Read and translate text A.

Text a. Suspension structures (I)

Technologically primitive societies use lines and ropes for suspension bridges. Beginning in the early nineteen century, suspension bridges began to be built of iron chains, and then bundled steel wire cables. The classic example of the modern suspension bridge is the Brooklyn Bridge, begun by John Augustus Roebling in 1867 and finished by his son, George Washington Roebling in 1883. In this bridge steel wire was used in the cables for the first time. It has remained the model for suspension bridges since its construction.

Only since 1955 has the principle of cables in tension been used extensively for buildings. A tension structure is especially efficient, since the entire cable is in tension, whereas most other structural forms have mixed stresses (as in a simple beam which is in compression along the top and in tension along the bottom). A suspended cable is an ideal structural form, for it is entirely in tension. In fact, if it were possible to freeze that form and invert it, the result would be a parabolic arch virtually entirely in compression. Such arches and vault forms derived from them, were used by the Spanish architect Antoni Gaudi last century in Barcelona, Spain.

Eero Saarinen also used suspension in a number of buildings. Saarinen put up a reinforced concrete parabolic arch the length of the rink, suspending cables from that arch down to curved walls on either side of the rink. A wooden roof deck was then laid on the cables, Saarinen enlarged on this idea in his Dulles Airport Terminal, outside Washington, D.C., 1958-62. Here two rows were created of outward-leaning columns, curving over at the top to carry beams running the length of the terminal. Between these two parallel beams, cables were suspended. Concrete slabs were placed on the cables to create the roof deck. This may not seem a lightweight structure, but the dead weight of the roof deck was necessary to keep the roof from fluttering in the wind.

Exercise 4. Translate the words:

deck, iron, bottom, parabolic, rope, chain, cable, model, tension, compression, vault, rink, column, top, length, beam, suspend, slab, row, wall, freeze, entirely, invert, result, side, carry, remain, construction.

Exercise 5. Choose the right translation from A to B:

A: iron, steel, deck, vault, derive, tension, chain, compression, cable, rope, top, bottom, length, side, row, beam, suspend, slab, weight.

B: длина, железо, ряд, подвешивать, плита, вес, сталь, свод, цепь, настил, заимствовать, растяжение, сжатие, трос, балка, кабель, нижняя часть, верхняя часть, сторона.

Exercise 6. Are these meanings correct or incorrect? Correct the mistakes:

flutter – вибрация

dead weight – мертвый вес

top – верхняя часть

deck – палуба

bottom – нижняя часть

live weight – временный вес

chain – цепь

tension – сжатие

parabolic – параболический

cable – кабель

derive – заимствовать

freeze – замораживать

wire – трос

arch – арка

Exercise 7. Translate the following word combinations:

dead weight, live weight, modern suspension bridge, steel wire cable, suspended cable, ideal structural form, reinforced concrete, parabolic arch, wooden roof deck, concrete slab, lightweight structure, mixed stresses.

Exercise 8. Guess the meaning of the following words:

steel, cable, model, efficient, result, arch, idea, terminal, parallel, parabolic, form, classic, primitive, column, principle, vertical, dilemma, crane, architect, central, material, diameter, section.

Exercise 9. Translate the sentences paying attention to Participle II.

1. We have mentioned about some problems connected with building.

2. Architects and engineers must be aware of the problems involved in laying foundations.

3. The engineer must collect undisturbed samples.

4. Other structural forms have mixed stresses.

5. Such vault forms derived from these structures were used by Antoni Gaudi last century.

6. These are solid shafts made by driving reinforced concrete deep into the ground.

7. Each pile may serve as a column with its foot driven into solid earth.

8. The truss extended in three dimensions becomes a space frame.

9. Substantial three-dimensional trusses built up of tubes of steel have a clear span of 342 ft.

10. The “geodesic dome” is built up of small light easily handled steel members.

11. Typically constructed of concrete shells can be very thick and heavy or extremely thin and light.

12. An interesting use of a folded shell is the Assembly hall at the University of Illinois Urbana.

13. These lateral forces are taken up by a belt of steel wire wound under tension around it.

14. These houses had roofs pitched inward towards the central open court.

15. Roman theatres derived from Greek models were the scene for the Greek plays.

Exercise 10. Read and translate text B with a dictionary. Make a plan.