а) Гражданское строительство – самая широкая область из всех областей строительства, часть из которого является самой старой областью строительства.
б) Гражданское строительство – самая широкая область из всех областей строительства частично и потому, что она является самой старой областью строительства.
в) Гражданское строительство – самая широкая область в строительстве именно потому, что она является самой старой областью строительства.
6. Continue the sentence:
1. Civil engineering is a broad field of engineering that deals with …
a) the planning of fixed structures only.
b) the maintenance of military structures.
c) the construction and maintenance of fixed structures or public works.
2. Civil engineering makes the world …
a) more irritable.
b) a more agreeable place for being lonely.
c) more attractive for living.
3. Civil engineering is the broadest of the engineering fields, …
a) partly because it is a very progressive field of engineering.
b) partly because it is a very ancient field of engineering.
c) partly because it is a very new field of engineering.
7. a) Complete the table:
| Noun | Verb | Adjective |
| constructive | ||
| agreement | ||
| developed | ||
| observe | ||
| maintaining | ||
| transportation | employed |
b) Choose the word from the table to complete the sentence:
1. Civil engineering makes the world a more … place in which to live.
2. Civil engineering is a broad field of engineering that deals with the … of fixed structures, or public works.
3. Engineering has developed from … of the ways natural and constructed systems react.
4. The … of empirical equations provide bases for design.
5. One of the tasks of civil engineering is to … public works.
6. Civil engineering deals with railways, water supply, sewer, … and traffic.
8. Scan the text and answer the questions:
1. What does civil engineering deal with?
2. What are fixed structures and public works related to?
3. Are bridges, roads, railways a part of structures that engineering deals with?
4. How may civil engineering be regarded?
5. What has engineering developed from?
6. What provides bases for design?
7. Is civil engineering the oldest or the newest of all engineering fields?
8. In how many fields was engineering once divided?
9. What is civil engineering comprised of?
Read and translate the text, do the exercises given below.
TEXT 2. AGGREGATES FOR CONCRETE
Study the words and word combinations
| 1) aggregates | - каменные материалы, заполнители бетона |
| 2) concrete | - бетон |
| 3) surround | - окружать |
| 4) bond | связывать |
| 5) binder | - связующее вещество |
| 6) rock | - камень |
| 7) denote | - означать |
| 8) filler | - наполнитель |
| 9) resisting | - сопротивление |
| 10) apply | - употреблять, применять |
| 11) percolation | - просачивание |
| 12) reduce | - уменьшать |
| 13) hardening | - затвердение |
| 14) sufficient | - достаточный |
| 15) impurities | - включения, примесь |
| 16) pebbles | - галька, мелкий щебень |
| 17) slag | - шлак |
| 18) cinder | - угольный мусор |
| 19) pumice | - пемза |
| 20) character | - качество, свойство |
| 21) tensile | - растяжимый |
| 22) span | - перекрывать |
| 23) sag | - оседать, падать |
| 24) bend | - гнуться |
| 25) edge | - край |
| 26) tension | - напряжение |
| 27) cross-section | - поперечное сечение |
| 28) incorporate | - вмещать |
| 29) reinforcement | - арматура |
| 30) devoid | - свободный |
| 31) exceed | - превышать |
| 32) pipe | - труба |
| 33) storage tank | - резервуар-хранилище |
AGGREGATES FOR CONCRETE
By the simple definition from the dictionary “aggregates are the materials, such as sand and small stones, that are mixed with cement to form concrete”. In other words aggregates (or cushioning materials) can be defined as a mass of practically inert mineral materials, which, when surrounded and bonded together by an active binder, form the rock. This rock is denoted by the general term concrete.
Aggregates have three principal functions in the concrete: they provide a relatively cheap filler for the concreting material, or binder; they provide a mass of particles which are suitable for resisting the action of applied loads, of abrasion, of percolation of moisture through the mass, and of climate factors; they reduce volume changes resulting from the action of the setting and hardening of the concrete mass.
All aggregates, both natural and artificial, which have sufficient strength and resistance to weathering, and which do not contain harmful impurities may
be used for making concrete.
As aggregates such natural materials as sand, pebbles, broken brick, gravel, slag, cinder, pumice and other can be used.
Prestressed Concrete
Prestressed concrete is not a new material. Its successful use has been developed rapidly during the last two decades, chiefly because steel of a more suitable character has been produced. Concrete is strong in compression but weak when used for tensile stresses.
If, therefore, we consider a beam made of plain concrete, and spanning a certain distance, it will at once be realized that the beam’s own weight will cause the beam to “sag” or bend. This sagging at once puts the lower edge of the beam of tension, and if the cross-sectional area is small, causes it to break, especially if the span is relatively large.
If, on the other hand, we use a beam of similar cross-section, but incorporate steel bars in the lower portion, the steel will resist the tensile stress derived from the sag of the beam, and thus assist in preventing it from breaking.
In prestressed concrete steel is not used as reinforcement, but as a means of producing a suitable compressive stress in the concrete. Therefore any beam (or member) made of prestressed concrete is permanently under compression, and is consequently devoid of crack under normal loading, or so long as the “elastic limit” is not exceeded.
Prestressed concrete is not only used for beams but is now employed extensively for columns, pipes, and cylindrical water towers, storage tanks, etc.