Глебовский Англ. яз. ч1 09

5.Important factors considered in deciding on a safety factor are listed here.

6.The description of new building materials was given in the article written by our specialist.

7.The bridge built over the river in1980 needed reconstruction.

8.The material is not efficiently used, and stresses are high.

9.Since the structures designed by engineers are planned to be stable, horizontal and vertical forces must be balanced.

10.Prestressed concrete is an improved form of reinforcement.

Упражнение 2. Переведите следующие словосочетания.

soil strata, surface temperature, glass fibre reinforcement, cross section dimension, climate and soil conditions, concrete structure design, basement floor, moisture content, shrinkage and temperature stresses.

Упражнение 3. Переведите следующие предложения, определите их главные и второстепенные члены.

1.With no basement these walls are not actually walls.

2.A sample subjected to a compressive force becomes shorter and wider.

3.The designer prepares plans consisting of drawings.

Упражнение4. Переведитеследующиепредложения, обращаявнимание на причастие I.

1.In practice the most serious changes causing failure of floors and roofs are dimensional ones.

2.Some structural materials having low thermal conductivity serve as insulation.

3.Various kinds of cement are available, for example, those having rapid hardening properties.

4.Forces acting at an angle are a combination of horizontal and vertical forces.

5.Stress is the force or pressure tending to strain or deform a structure or its various parts.

6.Heat movement takes place by conduction through any solid object separating areas of different temperatures.

Текст B

FOUNDATION WALLS

Foundation walls provide a ground-level edge for the building and support for elements of the building. In addition to these usual functions they often serve a number of functions for the building foundation system. Some of these are as follows:

Walls of some length and height typically form stiff beamlike elements. Their structural potential in these cases is often used for additional purposes: they distribute or equalize the load.

Walls may be used as spanning members, carrying their own weight as well as some supported loads. This is often the case in buildings with deep foundations and a column structure. Deep foundation elements are placed under the columns, and walls are used in order to span from column to column. This can also be the case with bearing foundations if the column footings are quite large and reasonably closely spaced; the stiff wall then is actually bearing not on its own footing but tends to span between the larger footings.

When columns occur in the same plane as a foundation wall, many different relationships for the structural action of the walls, columns, and column foundations are possible. If the walls and columns are monolithically constructed, the walls generally share the load to some extent.

Notes:

beamlike adj. похожий на балку spanning member ригель рамы

Ответьте на вопросы к тексту

1.What are the usual functions of the foundation walls?

2.What is the foundation wall structural potential often used for?

3.When are the walls used as spanning members?

4.In which case the walls and columns share the load to some extent?

Грамматические упражнения

Упражнение1. НайдитевтекстепричастияII. Определитеихфункцию и переведите на русский язык.

Упражнение 2. Найдите в тексте причастия I. Определите их функцию и переведите на русский язык.

Лексические упражнения

Упражнение 1. Переведите на русский язык приведённые ниже слова. Если Вы не знаете слово, найдите его в словаре. Выпишите из словаря то значение слова, в котором оно использовано в тексте.

closely spaced, equalize (v.), monolithically (adv.), relationship (n.), edge (n.), distribute (v.).

Упражнение 2. Найдите перевод слов списка А в списке В.

Упражнение 3. Напишите предложения с каждым из перечисленных ниже слов:

bear – bearing – bearing foundation

outside n. – outside adj. – outside adv. – outside prep.

ПрочитайтетранскрипциювспискеA, соотнеситееёссоответствующим словом из списка B и переведите слово на русский язык. Учтите, что не все слова списка В даны в списке А.

A

ТекстA

WALL FOOTINGS

Wall footings consist of concrete strips placed under walls. The most common type of wall footing consists of a strip with a rectangular cross section projecting an equal distance as a cantilever from both faces of the wall. For soil stress the critical dimension of the footing is the width of the footing bottom measured perpendicular to the wall face.

In most situations the wall footing is used as a platform upon which the wall is constructed. Thus a minimum width for the footing is determined by the wall thickness, the footing usually being made wider than the wall. With a concrete wall this additional width is used in order to support the wall forms while the concrete is poured. For masonry walls this added width assures an adequate base for the mortar bed for the first layer of the masonry units.

With relatively lightly loaded walls the minimum width required for platform depends on the allowable bearing stress on the soil. In this case, the short projection of the footing from the wall face will produce relatively transverse bending and shear stresses, permitting a minimum thickness for the footing and no transverse reinforcing. Most designers prefer, however, to provide some continuous reinforcing in the long direction of the footing, even when none is used in the transverse direction.

As the wall load increases the increased width of the footing required for the control of soil stress eventually produces significant transverse bending and shear in the footing. At some point this determines the required thickness for the footing and for required reinforcing in the transverse direction.

When the building has no basement and the floor consists of a concrete slab placed directly on the ground, these footings are sometimes poured monolithically with the floor slab.

Notes:

bearing stress напряжение смятия mortar bed растворная постель projection n. выступ

Ответьте на вопросы к тексту

1.What do wall footings consist of?

2.What is the most common type of wall footing?

3.How is the critical dimension of the footing calculated?

4.Is wall footing used as a platform?

5.What is a minimum width for the footing?

6.When is the additional width for the footing used?

7.What does the minimum width required for platform depend on?

8.What will the short projection of the footing from the wall face produce?

9.Where do most designers prefer to provide reinforcement of the footing?

10.When are footings poured monolithically with the floor slab?

Лексические упражнения

Упражнение 1. Переведите на русский язык приведённые ниже слова. Какие изперечисленныхслов могут быть другими частями речи? Какими именно? Как они в этом случае переводятся на русский язык?

project (v.), rectangular (adj.), long direction, transverse (adj.), cantilever (n.), platform (n.), face (n.), reinforcing (n.), floor slab, masonry unit.

Упражнение 2. Переведите следующие слова на английский язык:

напряжение сдвига; грунт; подвал; точка, момент; изгиб; основание; случай; ширина; направление; проектировщик; почва;

обеспечивать; лить, заливать; добавлять; использовать; определять; сооружать; измерять; состоять (из); класть, устанавливать; требовать; увеличивать(ся); обеспечивать, давать;

дополнительный; достаточный; минимальный; большинство; одинаковый; перпендикулярный; в конце концов; критический, решающий; поперечный; значительный; сплошной, неразрезной; относительно;

этот; чем; таким образом; как, в качестве; оба; иногда; когда; какой-то; первый; по мере того как.

Упражнение 3. Переведите данные существительные и образуйте сихпомощьюгруппысуществительных, характерныедлястроительной терминологии. Переведите их на русский язык.

Упражнение4. Какиеизуказанныхпереводовсловявляютсяошибочными. Укажите правильный перевод.

Грамматические упражнения

Упражнение1. Переведитеследующиепредложения, обращаявнимание на независимый причастный оборот.

1.A minimum width for the footing is determined by the wall thickness, the footing usually being made wider than the wall.

2.High level of sound absorption being required, porous material was used.

3.All the necessary materials being easily available, construction work in cast-in-place concrete started almost immediately.

4.Concrete elements can be precast on site, crane being used in order to lift them into their final position.

5.Deep foundation elements being placed under the columns, the walls are used in order to span from column to column.

6.The walls having been constructed, the workers left the site.

7.The horizontal forces must equal each other, there not being too much thrust either to the right or to the left.

8.A basement being required, foundation walls are quite high.

9.In order to produce compressive prestress the concrete member was placed between two abutments, pressure being applied with the jacks.

10.Structural carbon steel being cheap and convenient to use, it is the most important class of steel for the construction industry.

Упражнение2. Переведитеследующиепредложения, обращаявнимание на причастия I и II. Определите функцию причастий.

1.A property associated with concrete is shrinkage, which is the permanent contraction of concrete caused by loss of water after it hardens.

2.Plastics are widely used in construction having high strength to weight ratio and resistance to corrosion.

3.The total curing period is extremely long, that is, there is a steady gain in properties over time.

4.Form costs are much less with the concrete precast because the forms do not have to be supported.

5.Wood has a cellular structure looking like a number of tubes lain in the direction of the grain.

6.More water, more sand and less coarse aggregate, especially rounded coarse aggregate, make the mix more fluid but all these factors make the hardened concrete have more shrinkage and creep, and less durability.

7.Some materials, including concrete, continue to deform although there is no increase in load.

8.Having used toughened glass the designers overcame the typical drawbacks of this material.

9.The limiting strain depends on the level of stress.

10.The designer’s organization prepares plans consisting of drawings which show how the finished construction will look.

Текст B

The design of a symmetrical wall footing is done as follows:

1.Footing width is determined by the soil pressure limit, considering that the minimum width required for construction is not adequate for bearing. The usual design technique is to estimate a required footing thickness, find the width required for this footing thickness, check the footing stresses in order to assure the adequate thickness.

2.Since the reinforcing is not cheap, while concrete poured into a hole in the ground is relatively cheap, the footing thickness is usually not critical to compressive strength of the concrete. A thickness is selected that is adequate which means that it eliminates the need for shear reinforcing and minimizes the percentage of tensile reinforcing. The minimum footing is also necessary so as to place dowels for the wall reinforcing.

3.A reasonable minimum value is a steel area of 0.0015 times the gross concrete area, which is the minimum reinforcement required in a horizontal direction in walls. The distance of the reinforcing from the edges of the footing, which is called cover, must be a minimum of 3 in. if the edge is not

formed and 2 in. if the edge is formed. Reinforcing bars are usually of a low grade of steel, often the lowest grade available.

Notes:

gross area площадь брутто percentage n. величина (в процентах) pressure limit предел давления

shear reinforcing армирование для восприятия напряжений сдвига (среза) tensile reinforcing армирование для восприятия напряжений растяжения

Ответьте на вопросы к тексту

1.How is footing width determined?

2.What is the design technique used for that?

3.Why is the footing thickness usually not critical to compressive strength of the concrete?

4.What does adequate thickness mean?

5.How large should the cover be?

6.What grade of steel is usually used for reinforcing bars?

Грамматические упражнения

Упражнение1. НайдитевтекстепричастияII. Определитеихфункцию и переведите на русский язык.

Упражнение 2. Найдите в тексте причастия I. Определите их функцию и переведите на русский язык.

Лексические упражнения

Упражнение 1. Переведите на русский язык приведённые ниже слова. Если Вы не знаете слово, найдите его в словаре. Выпишите из словаря то значение слова, в котором оно использовано в тексте.

dowel (n.), symmetrical (adj.), minimize (v.), technique (n.), need (n.), cover (n.), estimate (v.), check (v.).

Упражнение 2. Найдите перевод слов списка А в списке В.

Упражнение 3. Напишите предложения с каждым из перечисленных ниже слов:

need n. – need v. minimum adj. – minimize v. project n. – project v.

ПрочитайтетранскрипциювспискеA, соотнеситееёссоответствующим словом из списка B и переведите слово на русский язык. Учтите, что не все слова списка В даны в списке А.

A

ТекстA

COLUMNS IN WALLS

A common problem in the design of building foundations is a foundation wall that must share its location with a row of columns. This takes place along the exterior walls of buildings with frame structures. When loads are transferred to the ground there are various possibilities for the relationships between the columns, the wall, and the foundation elements. The column loads may be light, as in the case of a one-storey building with light construction and short spans or the column loads may be large, as in the case of a multi-storey building. Type of Foundation. If the foundation consists of deep elements, either piers or groups of piles, the wall is usually designed as a spanning element of one type or another. When the foundation is of the shallow bearing type, there may be several possibilities for the column/wall/footing relationships.

Considering the wall by itself and ignoring the columns, the minimum wall footing according to our estimates is 11in. thick, 42in. wide. Thus, if we want to ignore the spanning potential of the wall, this would be the required footing for the wall between the column footings. For the column, if it were freestanding and not in the line of the wall, the required square footing would be 6ft2, 16in. thick. However, in this case even if it is decided to use a square footing, it would need to be larger, since it also supports part of the wall. And the larger it is, the more of the wall it supports. If we increase its size to 8ft2, the total load on the footing will be the column load of 100 k plus 8ft of the wall load at 10 k/ft, or a total load of 180 k.

Notes:

freestanding adj. свободностоящий ignore v. не принимать в расчёт

Ответьте на вопросы к тексту

1.What kind of a foundation wall is a common problem in the design of building foundations?

2.Where does this problem occur?

3.When are column loads light?

4.When are column loads large?

5.When is usually the wall designed as a spanning element?

6.How is the total footing load estimated in the example?

Лексические упражнения

Упражнение 1. Переведите на русский язык приведённые ниже слова. Какие изперечисленныхслов могут быть другими частями речи? Какими именно? Как они в этом случае переводятся на русский язык?

estimate (n.), row (n.), multi-storey (adj.), exterior (adj.).

Упражнение2. Переведитеследующие слова на английскийязык:

группа; случай; пролёт; этаж; возможность; каркаснаяконструкция; часть; местоположение; потенциал; натяжения; (лицевая) поверхность;

состоять из; передавать; происходить; требовать; решать; нуждаться; поддерживать; увеличивать; соединять; делить; проектировать;

другой; глубокий; лёгкий; неглубокий; несколько; различный; обычный; допустимый; общий; широкий;

в качестве; между; вдоль; сампо себе; согласно; таким образом; однако; так как; также; как.

Упражнение 3. Перечислите термины, характеризующие фундаменты: их типы, свойства и особенности, которые описаны в уроках 2.1–2.4. Дайте их перевод на русский язык.

Упражнение4. Какиеизуказанныхпереводовсловявляютсяошибочными. Укажите правильный перевод.

Упражнение 5. Прочитайте и переведите на русский язык следующие сокращения:

°C; ft2; in2; kPa; lb; psi; °F; k; MPa; psf.

Грамматические упражнения

Упражнение 1. Переведите следующие предложения, определите функцию инфинитива.

1.The stiff wall then is bearing not on its own footing but has tendency to span between the larger footings.

2.It becomes necessary to utilize the resistance of lower soil strata.

3.Concrete must be allowed to cure.

4.To overcome GRP flexibility is the purpose of double skin panels.

5.Wood is a very good material to cut and work.

6.GRP will creep, that is it will continue to deflect, if there is a permanent load on it.

7.When it is decided to build a structure an architect is asked to design the building project.

8.The materials to be selected by the builder will function under different conditions.

9.It is difficult to concrete a thin wall because the concrete has to be placed in the narrow opening at the top of the form.

10.The decision to use deep foundations should be done by building designers.

Упражнение2. Переведитеследующиепредложения, обращаявнимание на сравнительный оборот the … the … .

1.The shorter the route taken by a load to its foundations and the fewer the elements involved in so doing, the greater the economy of the structure.

2.The larger a square footing is, the more of the wall it supports.

3.The more the compressive force is the shorter a rubber band subjected to it becomes.

4.The higher thermal conductivity of the material is the lower is the rate of heat movement which takes place by conduction through any solid object that separates areas of different temperatures.

Упражнение3. Переведитеследующиепредложения, обращаявнимание на условные придаточные предложения.

1.If beams which support a roof can’t withstand loads that they have to carry they will break.

2.If the beam itself didn’t have sufficient strength to counterbalance the weight it support from above it would fail.

3.It would become necessary to utilize the resistance of lower soil strata if the soil at the bottom of the building were not adequate for the load transfers.

4.If a force remains constant, the actual unit stress will change with the change of the cross section.

Упражнение4. Переведитеследующиепредложения, обращаявнимание на причастия I и II. Определите функцию причастий.

1.While choosing the type of foundation for a building, designers should consider the soil structure on the site.

2.Applying a film or coating to a fabric we can improve its properties.

3.Significantly reduced cost of cast-in-place concrete was achieved by the constant re-use of formwork.

4.Tendons placed along the centroidal axis are rare.

5.When applied to the beam, loads produce both tensile and compressive stresses at the middle of the span.

6.Welding the steel members the builders made the connection strong.

7.The materials used allowed minimum work on the site.

8.Materials having very low density are used for thermal insulation.

Текст B

USE OF PEDESTALS

There are many cases in which a short compression element, called a pedestal, is used as a transition between a footing and some supported element. Some of the purposes for pedestals are the following:

If the bearing area on the top of the footing is widened, the pedestal will achieve a reduction in the shear and bending stresses in the footing, permitting the use of a thinner footing.

To permit the use of a lower-strength concrete in the footing, it may be possible to use a pedestal with a strength that is transitional between the column and the footing.

The use of a pedestal may allow the doweling of large columnreinforcing bars within the pedestal height. The pedestal reinforcing may then be done with bars.

When the bottom of the footing must be some distance below the ground surface, a pedestal may be used in order to keep vulnerable elements above ground.

Pedestals of masonry or concrete are essentially short columns. When carrying major loads, they should be designed as reinforced columns with required vertical reinforcement, ties, and dowels. When loads are light and the pedestal height is less than three times the thickness, however, they may be designed as unreinforced elements. If built of hollow masonry units (concrete blocks, etc.) they should have the voids completely filled with concrete.

Notes:

bearing area опорная поверхность, опорная площадь bending stress напряжение при изгибе

pedestal n. подколонник

reduction n. снижение, уменьшение, ослабление transitional adj. переходный

Ответьте на вопросы к тексту

1.What kind of element a pedestal is?

2.What is it used for?

3.What are the reasons for the use of pedestals?

4.How should pedestals be designed when carrying major loads?

5.How should they be designed when loads are light?

6.When should pedestals have the voids filled with concrete?

Грамматические упражнения

Упражнение1. Найдитевтекстеинфинитивы. Определитеихфункцию и переведите на русский язык.

Упражнение 2. Найдите в тексте причастия I и II. Определите их функцию и переведите на русский язык.

Лексические упражнения

Упражнение 1. Переведите на русский язык приведённые ниже слова. Если Вы не знаете слово, найдите его в словаре. Выпишите из словаря то значение слова, в котором оно использовано в тексте.

hollow (adj.), the following (n.), vulnerable (adj.), essentially (adv.).

Упражнение 2. Найдите перевод слов списка А в списке В.

Упражнение 3. Напишите предложения с каждым из перечисленных ниже слов:

equal – equally – equalize follow – as follows – the following

136

Текст C

DEEP FOUNDATIONS

In most cases deep foundations are utilized only where it is not possible to have shallow foundations. The decision to use deep foundations, the selection of the type of system, and the design of the elements of the system should all be done by building designers with considerable knowledge and experience in foundation design, including knowledge of the types of systems, their capabilities and drawbacks, and some of the problems connected with the use of such systems for building foundations.

Need for deep foundations

The most common reasons for the use of deep foundations are the following:

1.Lack of Adequate Soil Conditions for Bearing Footings. There are a number of soil conditions that may make the usual bearing foundation elements near the bottom of the building not possible. The deep foundation thus is used essentially in order to reach a desirable bearing level at some distance from the bottom of the building.

2.Heavy Loads on the Foundations. In some cases the soil at upper levels may be sufficient for the use of bearing elements for relatively light loads, but the size of footings required, the need for limited settlement, or other factors occurring with extremely heavy loads, may require a deep

foundation. High-rise buildings, long-span structures, and construction of massive elements of concrete or masonry are cases in which loads may become considerable and may be above the simple bearing capabilities of ordinary soils.

3. Instability of Ground-Level Soil. Use of deep foundations may be necessary where soil at the level of the bottom of the building is subject to some forms of change in the soil structure or the general state of the soil mass. This situation sometimes occurs at waterfront and hillside locations. In these cases the use of deep foundations is necessary in order to anchor the building to a more reliable, stable ground mass.

4. Support of Structures Sensitive to Settlement. In some situations, settlement of foundations is highly critical. Examples are buildings with stiff rigid frame structures and buildings housing equipment that requires precise and continuous alignment. Bearing foundations will settle on almost any soil other than solid bedrock. Deep foundations tend to have little settlement,

137

especially when the elements are bearing on rock or on a highly consolidated soil stratum.

Deep foundations are usually used only in situations in which shallow footings are not possible. The primary reason is cost. Where ordinary footings can be used and their size is not excessive, the cost of deep foundations will rarely be competitive. If footings are possible but their size is excessive, it may be necessary to perform a cost analysis of alternatives. Such an analysis will usually require relatively complete designs of the alternate systems and can be difficult when the alternate foundation systems require significant differences in the building structure.

Foundation design and construction practices are often influenced by the location of a building. This may be partly because of the local climate and soil conditions. Where there is some history of construction in the area, however, it may also be due to local experience with particular foundation systems or construction techniques.

Most deep foundation elements, piles or piers, are constructed by special foundation contractors.

Notes:

alignment n. выравнивание consolidate v. укреплять history n. история

sensitive adj. восприимчивый waterfront n. береговая линия

Ответьте на вопросы к тексту

1.What kind of knowledge and experience should a building designer possess to use deep foundations?

2.What are the most common reasons for the use of deep foundations?

3.What are the typical structures requiring deep foundations?

4.Why are deep foundations used in situations in which shallow footings are not possible?

5.When is a cost analysis of alternatives necessary?

6.What will such an analysis usually require?

7.Why is foundation design and construction practices often influenced by the location of a building?

8.Who are deep foundation elements constructed by?

Лексическое упражнение

В списке А даны некоторые слова и выражения, которыеиспользованы в тексте для домашнего чтения. Найдите их перевод в списке В.