К теме «Building Materials and Their Properties»
TIMBER
Timber is the most ancient structural material. In comparison with steel timber is lighter, cheaper, easier to
work and its mechanical properties are good. On the other hand, timber has certain disadvantages. First, it burns and
is therefore unsuitable for fireproof buildings. Second, it decays.
At present an enormous amount of timber is employed for a vast number of purposes. In building timber is
used too.
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, wallplates, for
temporary buildings and unpainted internal woodwork.
Timber cannot be used for either carpenters’ or joiners’ 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 tendency to decay. Elimination of moisture increases the strength,
durability and resilience of timber.
timber – лесоматериал; пиломатериал; лес; древесина
softwoods – древесина мягких пород
hardwoods – древесина твёрдых пород
paneling – обшивка панелями
veneering – обшивка фанерой
internal woodwork – внутренняя деревянная отделка
joiner – столяр
to fell – рубить (дерево)
sap – древесный сок
resilience – упругость; эластичность
STONE
Stone has been used as a structural material since the earliest days. Almost all famous buildings of classic
times, of the medieval and Renaissance periods and of the eighteen and early nineteenth centuries were erected of
stone. The art of making any structure in stone is called stone masonry. In some places stone was used because of
the scarcity of timber, but in other places stone was preferred because of its durability.
The stones which are usually used for masonry work are as follows:
1. Granite. Granite is very hard, strong and durable. It is used particularly for basements, base courses,
columns and steps and for the entire facades. Its colour may be gray, yellow, pink or deep red.
2. Sandstone. Sandstone is composed of grains of sand or quarts cemented together. Sandstones form one of
the most valuable materials. The durability of sandstones depends very largely upon the cementing material. Thus
there are different kinds of sandstones. Many sandstones are exceptionally hard and are selected for steps, sills, etc.
It is an excellent material for concrete aggregate.
3. Marble. Marble is a crystalline stone chiefly used for decorative purposes. White and black marbles are
used for ornamental decoration where the beauty of the marble is shown to its best advantage.
stone masonry – каменная кладка
scarcity – недостаток; нехватка
base course – нижний ряд кладки; цоколь
sandstone – песчаник
sill – порог; подоконник
marble – мрамор
_____________________________________________________________________________________________
_________ is one of the oldest, most durable and most respected of building materials. Traditionally, it is the _________ chosen by both
architects and engineers when permanence, enduring color and texture, and complete freedom from deterioration and maintenance are prime
requirements.
And granite is ageless – always contemporary. Today's leading architects, knowing its unique _________ , are using it more extensively
than ever before. Many of our most impressive buildings, commercial as well as institutional and monumental, are being faced with granite, and
it's still unequaled as a material for steps, terraces, and the pavings of plazas and public spaces.
The granite industry is keeping pace with architectural progress and changing demands. Technological developments have revolutionized
quarrying* (добыча) and fabrication _________ , reducing costs and leading to new applications. Attractive new finishes* (способы шлифовки),
new construction techniques and new jointing methods have been _________ . For example, granite is being employed on steel frames to provide
preformed wall units which require no additional masonry back-up.
It is common _________ in the industry to classify architectural granite as either of two _________ :
Building Granite: granite used either structurally or as a veneer for exterior or interior wall facings, steps, paving, copings or other
building features.
Masonry Granite: granite used in larger blocks for retaining walls, bridge piers, abutments* (опоры моста), arch stones and similar
_________ .