A
1. Is glass a new building material?
2. What is glass made of?
3. What sort of equipment is necessary for producing glass?
4. When was glass brick invented?
5. Where is glass used in modern construction?
B
1. What is plastic and what is this material usually derived from?
2. What is the most common property for all types of plastics?
3. Where are plastics applied in modern construction?
4. What are the main advantages of plastics as a building material?
5. Can plastic displace traditional building materials in future? How can you prove your opinion?
READING FOR TEST “BUILDING MATERIALS”
Translate the text without using the dictionary.
THE OPTIONS OF USING TIMBER,
CONCRETE AND STEEL
There are three of the most common building materials in the world: steel, concrete, timber.
STEEL
Steel products are ones of the most widely used building materials in construction today, mainly because they are diverse, durable, and available, and no matter what kind of project you are working at.
Steel as a structural material has a high strength/weight proportion; the dead weight (собственный вес) of steel structures is relatively small. This property makes steel a very attractive structural material for:
· high-rise buildings;
· long-span bridges;
· structures located on soft ground.
Ductility. Steel can undergo large plastic deformation beforefailure, thus providing a large reserve strength. This property is referred to as ductility. Properly designed steel structures can have high ductility, which is an important characteristic for resisting shock loading such as blasts (взрыв) or earthquakes. A ductile structure has energy-absorbing capacity and it will not be suddenly collapsed. It usually shows large visible deflections (прогиб, отклонение) before failure or collapse.
Properties of steel can be predicted with a high degree of certainty. Steel in fact shows elastic behavior up to a relatively high and usually well-defined stress level. Steel properties do not change considerably with time.
Advantages of steel.
· Steel structures can be erected quite rapidly.
· Steel structures in general can be repaired quickly and easily.
· Steel is highly suitable for prefabrication and mass production.
· Steel can be reused after a structure is disassembled.
· Steel buildings can be easily expanded by adding new bays or wings. Steel bridges may be widened.
· Steel structures have relatively good fatigue (усталость) strength.
Disadvantages of steel in certain cases.
Steel structures may be more costly than other types of structures.
· The strength of steel is reduced when heated at temperatures commonly observed in building fires. Also, steel conducts and transmits heat from a burning part of the building quite fast. Consequently, steel frames in buildings must have adequate fireproofing.
· Steel structures are subjected to air, water and corrosion and should be painted regularly. Application of weathering and corrosion-resistant steel may eliminate this problem.
· Steel members are in general more subjected to deformation than reinforced concrete compression members.
TIMBER
The building industry is increasingly recognising the potential results available from working with environmentally focused products i.e. timber, that combine clean aesthetics and structural properties.
Advantages of timber.
· Timber is an excellent insulator: brick-built houses are also known to have outstanding insulating properties, but timber surpasses them.
· Timber is an elastic material: in comparison with brick or concrete walls, timber walls don’t have to be very thick. A 20 cm wall, for example, is strong enough to protect against the winter cold, if it has a proper treatment.
· Timber houses are very attractive; they don’t need special decorative finishes.
Disadvantages of timber.
·Timber is vulnerable (уязвимый) to vital forces like termites (термиты), woodworms (личинки древоточца) or wood ants (муравьи).
·Natural forces like the sun, fire, water and etc. can have unfavorable effect on timber.
·Timber is subjected to shrinking (усадка) and swelling (набухание, вспучивание). Timber has a natural ability to absorb water which is also known as hygroscopy.
CONCRETE
Concrete is an artificial stone-like material used for various structural purposes. It is made by mixing a binding material as cement and various aggregates i.e. inert materials, such as sand, crushed stone, pebbles (галька, мелкий булыжник), gravel, shale, etc with water and allowing the mixture to harden by hydration (гидратация – присоединение воды к...).
Advantages of concrete.
· Concrete is economical when ingredients are readily available.
· Long life of concrete and relatively low maintenance requirements increase its economic benefits.
· It is not subjected to corrosion or decay as other building materials.
· Concrete has the ability to be moulded or cast into almost any desired shape.
Concrete is non-combustible material which makes it fire-safe and able to withstand high temperatures
· It is resistant to wind, water, and insects. Therefore, concrete is often used for storm shelters.