Пособия / english-for-builders-and-architects

4. Why do people like brick houses?

20 Read the text and say what category of bricks is preferable in the territory you live in according to the climate conditions in and why:

FROST RESISTANCE

Bricks are classified into one of the three categories, F2, F1 and F0 according to their frost resistance within a standardized freezing test (Table 3.2).

Only category F2 bricks are totally resistant to repeated freezing and thawing when in a saturated condition. Category F1bricks are durable, except when subjected to repeated freezing and thawing under saturated conditions. Therefore, category F1 bricks should not be used in highly exposed situations such as below dampproof courses, for parapets or brick-on-edge copings, but they are suitable for external walls which are protected from saturation by appropriate detailing. Category F0 bricks must only be used where they are subject to passive exposure, as when protected by cladding or used internally.

21 Topics for projects and presentations:

1.Optimal dimension, characteristics, and strength.

2.Brick tinting.

3.World masterpieces made of brick.

4.Concrete bricks and concrete brickworks.

5.Calcium silicate bricks.

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sand, gravel, and water to turn into a solid

3. lime 3.c) a mixture of cement, water, sand and gravel (stones, crushed rock)

2 Read the following information and offer your ideas of further development and usage of cement:

Современный цемент был изобретен сравнительно недавно. В 1822 году после Отечественной войны 1812 года, Москва стремительно строилась. К вновь возводимым каменным зданиям предъявлялись повышенные требования по прочности и надежности. Деревянных построек после памятного пожара, который устроили отступающие французы, старались не возводить. Русский строитель Егор Челиев (по некоторым данным Делиев), проводя эксперименты с обожженным составом извести и глины, получил сухую строительную смесь способную затвердевать в воде до состояния камня. Так был изобретен современный цемент.

3 Discuss the following:

4 a) Transcribe the following words:

hydraulic cement, carbon dioxide, lime mortar, aqueduct, artificial pozzolanas, argillaceous, calcium carbonate, carboniferous, iron oxide, polypropylene fibres.

b) In what context do you think the following words and phrases will appear in the text?

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content at extraction, four key variations in the manufacturing process have been developed: the wet, semi-wet, semi-dry and the dry processes.

Concrete is a mixture of cement, aggregates and water together with any other admixtures which may be added to modify the placing and curing processes or the ultimate physical properties. Initially, when mixed concrete is a plastic material, which takes the shape of the mould or formwork. When hardened it may be a dense, loadbearing material or a lightweight, thermally insulating material, depending largely on the aggregates used. It may be reinforced or prestressed by the incorporation of steel.

Most concrete is crushed and recycled at the end of its useful life, frequently as hard core for new construction work. However, a growth in the use of recycled aggregates for new concrete can be anticipated, as this will have a significant environmental gain in reducing the demand on new aggregate extraction.

Aggregates for concrete are normally classified as lightweight, dense or high-density. Standard dense aggregates are classified by size as fine (i.e. sand) or coarse (i.e. gravel). Additionally, steel or polypropylene fibres or gas bubbles may be incorporated into the mix for specialist purposes.

Natural stone aggregate concretes typically have densities within the range 2200–2500 kg/m3, but where densities below 2000 kg/m3 are required, then an appropriate lightweight concrete must be used.

The three general categories of lightweight concrete are lightweight aggregate concrete, aerated concrete and no-fines concrete (Fig. 4.2).

Figure 4.2. Lightweight concretes

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плавление; включение (добавление) стали; щебень; восприимчивый к разрушению от мороза.

8 Read and translate the text and make 5 questions to it:

Portland cement is produced from a slurried mixture of limestone and clay, burned at a high temperature in a kiln and the resulting clinker is then ground up, with ground calcium sulphate added to regulate its set. It is highly processed partly to ensure no variation in product.

The essential feature of a lime mortar or plaster is that it needs to carbonate in order to cure. A transformation takes place within it as calcium hydroxide changes to calcium carbonate, a process that requires moisture, as carbon dioxide in the atmosphere has to be carried into the lime plaster in solution. A hydraulic lime has the extra feature of also having a chemical set, so that it can feel hard to the touch within a few hours to a couple of days, depending on the strength of the hydraulic lime. It can remain workable for several hours or days, but it still needs to carbonate after it has set. Lime strengths vary greatly depending on the type of lime used, but it takes about 28 days to reach full strength.

Cement does not carbonate. It hardens because of a chemical reaction with water, usually setting within half an hour to an hour, after which time it cannot be re-worked. It takes about 28 days to reach its full strength, and is generally very much stronger than lime.

LANGUAGE FOCUS

9 Use the words below to complete the sentences:

Cement is a bonding agent used in conjunction with sand, water, and 1) _____ (crushed stone) to create mortar and/or concrete. You need cement for a variety of projects – to set 2) _____ for decking or fences, to fill a sidewalk, or to patch a blemish in your house's foundation. If you are doing a project that requires concrete or 3) ) _____ application, you will need to know how 4) _____ the cement that bonds the materials together. It's a good idea to take a look at the Decorate Concrete Overlay Guide - – you'll learn 5) _____ that can improve the look of everything from concrete steps to sidewalks and more! Here is how you mix cement.

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