Пособия / Л.П. Даниленко, Ю.Ю. Сильман TECHNICAL ENGLISH FOR CIVIL ENGINEERS AND STRUCTURAL DESIGNERS

to compress – сжимать, сдавливать

to subject to smth. – подвергать воздействию to reinforce – усиливать, укреплять, армировать to collapse – разрушиться, рухнуть

Task. Read and translate the text, do the exercises given below.

TEXT 1. BUILDING MATERIALS

Building materials are materials used for different purposes in construction. They have certain advantages and disadvantages, which are taken into account when designing a structure. They should meet several requirements. In most cases it is important that they should be hard, durable, fire-resistant and easily fastened together. The most commonly used materials are steel, concrete, stone, timber, brick, metal, glass and plastics. They differ in hardness, durability, fire-resistance, weight, strength, and cost. Wood, stone, sand, lime, clay are the examples of natural materials. Cement, concrete, brick, glass, plastics are referred to artificial i.e. man-made materials.

All building materials are divided into three groups.

1.Main building materials used for bearing structures, such as timber, rock, artificial stones, different metals.

2.Cementing i.e. binding materials used for joining different planes such as lime, gypsum and cement.

3.Secondary i.e. auxiliary materials used for the interior finish of the structure such as glass, plastics, laminate, ceramics.

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Ex. 3. Classify the properties of building materials listed below as advantageous and disadvantageous.

Advantages:

Disadvantages:

High cost, low water-resistance, heat-insulation, fire-resistance, light weight, durability, low strength, hardness, low cost, corrosion-resistance, heavy weight, softness, high strength, non- fire-resistance, sound insulation.

Ex. 4. Choose from the block the antonyms for the following adjectives:

Natural, light, exterior, cheap, disadvantages, weak, primary, combustible, unstable, main, soft.

Task. Look through the text and tell about timber.

TEXT 2. TIMBER

Timber is the most ancient structural material. On the one hand if we compare steel and timber, the latter is lighter, cheaper, easier to work and its mechanical properties are good. On the

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other hand timber has certain disadvantages. Firstly, it burns and is thereforeunsuitable forfireproofbuilding.Secondly,itdecays.

Timber is a name applied to the cut material derived from trees. Timber used for building purposes is divided into two groups: softwoods* and hardwoods*. Hardwoods are chiefly used for decorative purposes, as for paneling*, veneering in furniture*, and some of them are selected for structural use because of their high strength and durability. In modern construction timber is often used for window and door frames, flooring, fences and gates, wall plates, for temporary buildings* and unpainted internal woodwork.

Timber cannot be used for work immediately it has been felled because of the large amount of sap* which it contains. Most of this moisture must be removed; otherwise the timber will shrink* excessively, causing defects in

the work and a strong tendency to decay. Elimination of moisture increasesthestrength*,durabilityandelasticityof timber.

Notes:

softwoods – древесина мягких пород, хвойная древесина hardwoods – твердая древесина, древесина твердых пород paneling – обшивка панелями

veneering in furniture – облицовка мебели temporary building – временная постройка sap – сок

to shrink – давать усадку strength – прочность

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EXERCISES

Ex. 1. Ask your group-mates the following questions.

1.Is timber a very ancient structural material?

2.What are the advantages and disadvantages of timber in comparison with steel?

3.What two groups is timber used for building purposes divided into?

4.What purposes is timber often used in modern construction for?

5.Why cannottimberbeusedimmediately it hasbeen felled?

6.What increases strength, durability andelasticity of timber?

Ex. 2. Say ifthe sentences given below aretrue or false.

1.Timber is a comparatively new material.

2.Timber asabuildingmaterial hasnoonedisadvantage.

3.Mechanical properties of timber are good.

4.Softwoods are mainly used for decorative purposes.

5.Hardwoods are characterized by durability and high strength.

6.Builders can use timber in their work just after trees have been felled.

Ex. 3. Complete the following sentences.

1.Timber is lighter, cheaper, easier in work than…

2.Timber has two disadvantages, they include…

3.Timber is a name we apply to the cut material derived from…

4.In modern construction timber is widely used for …

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5.Before starting work with wood one should remove the moisture which trees contain because…

6.For paneling and veneering in furniture builders often use …

Task. Revise active vocabulary and translate the text without using the dictionary.

TEXT 3. CEMENT AND CONCRETE

Cement and concrete are among the most important building materials. Cement is a fine, grey powder. It is mixed with water and materials such as sand, gravel, and crushed stone to make concrete. The cement and water form a paste that binds* the other materials together when the concrete hardens.

Nearly all the cement used today is Portland cement, which is hydraulic cement or one that hardens under water. This cement was named Portland because it has the same texture as the natural stone quarried on the Isle of Portland, a peninsula on the south of Great Britain.

Concrete goes into the making of many things today – house foundations, wall blocks, ceiling slabs and entire prefabricated units. The material falls into several classes: very heavy, heavy, light and very light and they differ in density, mechanical strength, fillers, etc. However, they all have one property in common such as heat insulating capacity. This property is controlled by the coefficient of thermal resistance: the higher it is, the less heat escapes from the room and the lower the heating costs run up by the owner.

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Concrete is fireproof, watertight, comparatively cheap, and easy to make. When first mixed, concrete can be moulded* into almost any shape. It quickly hardens into an extremely strong material keeps the strength for a long time, and requires little care.

Uses of cement and concrete

Nearly all skyscrapers, factories and many houses stand on concrete foundations. These buildings may also have concrete frames, walls, floors, and roofs. Concrete is used to build dams to store water and bridges to span rivers. Cars and trucks travel on concrete roads and airplanes land on concrete runways. Concrete tunnels run through mountains and under rivers. Concrete pipes distribute water, carry away sewage*, drain farmland, and protect underground telephone wires and electricpower lines.

Kinds of concrete

•ordinary concrete – обычный бетон

•dense concrete – плотный бетон

•heavy concrete – тяжелый бетон

•prefabricatedconcrete–бетон заводскогоизготовления

•ready-mixed concrete – готовый бетон

•cast-in-situ concrete – монолитный бетон

•prestressed concrete – предварительно-

напряженный бетон

•reinforced concrete – железобетон

•precast concrete – сборный бетон

•lightweight concrete – легкий бетон

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•aerated concrete – ячеистый бетон

•high-early-strength concrete – бетон быстрого твердения

•foam concrete – пенобетон

Reinforced concrete is made by casting concrete around steel rods* or bars*, and steel strengthens concrete. Almost all large structures require this extra-strong type of concrete.

Prestressed concrete usually is made by casting concrete around steel cables* stretched by hydraulic jacks*. After concrete hardens, the jacks are released* and the cables compress concrete. Concrete becomes the strongest when it is compressed. Steel cables can also be bent* into an arc, so that they develop a force in any desired direction, such as upward* elements in a bridge. Prestressed concrete beams*, roofs, floors are often cheaper for some uses than those made of reinforced concrete.

Precast concrete is cast and it hardens before being used for construction. Precasting firms make concrete sewer pipes*, floor and roof units, wall panels, beams, and girders*, and transport them to the construction sites. Sometimes builders make such pieces at the construction site and hoist them into place after they hardened. Precasting makes possible the production of concrete building elements.

Aerated concrete contains tiny air bubbles*. These bubbles are formed by adding half brick* like resinous* or fatty* materials to the cement, or to the concrete when it is mixed. The bubbles give the water in concrete enough space to expand as it freezes. The bubbles also protect the surface of the

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concrete from chemicals used to melt ice. Such qualities make aerated concrete a good material for roads and airport runways.

High-early-strength concrete is chiefly used in cold weather. Concrete is made with high-early-strength Portland cement, and it hardens much more quickly than ordinary concrete. High-early-strength concrete is often cheaper to use, because it cuts the amount of time necessary for its hardening.

Lightweight concrete weighs less than other kinds of concrete. Builders make it in two ways. They may use lightweight shale*, clay, pumice*, or other materials instead of sand, gravel, and crushed stone. Or they may add chemicals which foam and produce air spaces in the concrete when it hardens. These air spaces are much larger than the air spaces in aerated concrete.

Foam concrete is one of the lightest varieties of the mineral. Various processes are used to make it. One of them relies on natural porous fillers (gravel and crushed stone) and their artificial substitutes (expanded clay aggregate).

Notes:

to bind – связывать; крепить

to mould – формовать; отливать в форму sewage – сточные воды

rod – арматурный стержень

bar – арматурный пруток/стержень steel cable – стальной трос

hydraulic jacks – гидравлический домкрат to release – расцеплять, отсоединять

to bend – гнуть, изгибать

upward – поднимающийся вверх, восходящий beam – балка

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half brick – кирпич-половняк

resinous material – смолистый материал fatty material – смазочный материал sewer pipe – сточная труба, коллектор girder – балочная ферма, балка bubbles – пузыри (воздуха или газа) shale – сланец

pumice – пемза

EXERCISES

Ex. 1. Match the words and word-combinations with their definitions.

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