1.1
A, B . , .
A
['fLs]; ['rst]; ['mLtq]; ['kPlqm]; ['tenSqn]; [brIk]; [rPd]; ['dIfIkqlt]; [ju:s]; [ju:z]; ['ndq]; [sænd]; [æz]; [' kPnstqnt]
B
| us sand use n. rest | force constant mortar different | send under comb tension | break rod difficult rust | column brick use v. as |
A
Building materials of the past were wood and masonry - brick, stone, or tile, and similar materials. The builders bound the layers together with mortar or some other binder. They sometimes used iron rods to strengthen their buildings. The columns of the Parthenon in Athens, for example, have holes in them for iron bars that have now rusted away. The Romans used natural cement that they made from volcanic ash.
Steel and cement, the two most important building materials now, appeared in the nineteenth century. People had been producing steel, an alloy of iron and an amount of carbon, up to that time by a difficult process that limited its use. After the invention of the Bessemer process steel was available in large quantities.
The important advantage of steel is its tensile strength; that is, it does not lose its strength when it is under a calculated degree of tension - a force which pulls materials apart. New alloys have further increased the strength of steel and eliminated some of its problems, such as fatigue, which is a tendency for it to weaken as a result of constant changes in stress.
Modern cement, which we call Portland cement, appeared in 1824. It is a mixture of limestone and clay. Builders mix it with sand, aggregate (stones, crushed rock, or gravel), and water to make concrete. Different proportions of these materials produce concrete with different strength and weight. Concrete is very versatile; builders can pour, pump, or spray it into all kinds of shapes. And while steel has great tensile strength, concrete has great strength under compression. Thus, the two building materials complement each other.
Notes:
Athens n. ['xTqnz]
Bessemer process n. ['besImq ֽprqVses]
complement v.
invention n.
Parthenon n. ['pRTinqn]
pump v. , ()
Roman n.
volcanic ash n.
.
1. What were the main building materials of the past?
2. What did the builders use to bind the layers together?
3. Who used iron rods to strengthen their buildings?
4. Which columns have holes for iron bars?
5. Who used natural cement?
6. When did the two most important building materials appear?
7. When was steel available in large quantities?
8. What is the important advantage of steel?
9. What has increased the strength of steel?
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10. When was Portland cement invented?
11. What is Portland cement?
12. What do builders do to make concrete?
13. What makes concrete a versatile building material?
14. Why do concrete and steel complement each other?
1. )
:
advantage, aggregate, alloy, amount, bar, binder, brick, builder, building, carbon, cement, change, clay, column, compression, concrete, crushed rock, degree, fatigue, force, gravel, hole, iron, kind, layer, limestone, masonry, mixture, mortar, Portland cement, proportion, quantity, rod, sand, shape, steel, stone, strength, stress, tendency, tensile strength, tension, tile, time, use, weight, wood, result
:
available, constant, different, difficult, further, important, modern, natural, similar, sometimes, together, versatile, all
:
after, as, for, from, some, such as, thus, under, which, while, when, for example, that is, each other, other, now, together
:
appear, bind, calculate, eliminate, increase, lose, mix, pour, produce, pull, pull apart, rust, spray, strengthen, limit
) ? . , ed.
2. :
; , ; ; , ; , ; ; , ; , ; ; , ; ; , ; , , ; ; ; ; , ; , ; ; ; ; ;
; ; , ; ; , ; (); , ;
; , ; ; ; , ; , ; ; ; , ; , ; ;
; ; ; ; ; ; ; .
3.
4. .
| wood rod pull limestone iron proportion alloy some advantage increase from pour | quantity clay tension sometimes while different hole kind mix weight masonry steel | , , |
5. , . . , .
| stress rust change heat increase process | , , | use result plan work amount function |
|
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1. , :
1. For centuries the main building material in Russia was wood.
2. We will go to the cinema on Sunday.
3. Steel and cement have been the most important construction materials.
4. He is reading a book now.
5. She did not go to school yesterday.
6. People had been using steel before the invention of the Bessemer process.
7. This material lost its strength.
8. Steel has advantages which make it a good building material.
9. New materials for building have appeared.
10. They will have finished the work by tomorrow.
2. to have .
1. The builders have to finish the work.
2. They dont have a computer at home.
3. John had finished his homework when we came.
4. New alloys have further increased the strength of steel.
5. Concrete has great strength under compression.
6. Wood, iron and stone have different tensile strength.
7. The builders have used new materials.
8. The builders had to strengthen the column.
3. , , , :
1. The builders bound the layers together with mortar.
2. Steel and cement appeared in the nineteenth century.
3. The important advantage of steel is its tensile strength.
4. New alloys have further increased the strength of steel.
5. Different proportions of the materials produce concrete with different strength and weight.
4. , s-endings.
1. The Romans used natural cement.
2. These are Johns books.
3. Concrete loses its strength under tension.
4. Good results are available when the builder selects and uses these materials.
5. Jane sometimes goes to the cinema with her friends.
5. :
| advantage bar brick century | foot man process quantity | result stress weight woman |
.
B
People build every building project in order to get a structure which will function for some time. Good results depend upon the materials which the builder selects and how he uses them. They have to function under different conditions. The builder has to understand building materials in order to produce the satisfactory structure. He needs to know design procedures, building methods, and maintenance. In the basis of all these is the knowledge of materials. In order to be satisfactory, each material that a builder uses must function well over a long time.
The building process begins when a person or organization, the owner, decides to build a structure.
The next step is to ask a designer, either an engineer or an architect, to design the building project. The designer makes plans which consist of drawings. These drawings show how the building will look. The plans explain what materials a builder will use. The designer also explains the characteristics which the materials must have. He describes all basic materials, such as wood, iron, and stone, and all manufactured products, such as concrete blocks.
The owner then asks a builder to do the building work and gives him a contract to build a structure according to the plans which an engineer or an architect has made.
Notes:
maintenance n.
owner n.
satisfactory adj.
|
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.
1. Why is the knowledge of the building materials important?
2. What are the steps of building a structure?
3. Who designs a building project?
4. What is the function of the builder?
1. ?
2. to have?
3. s?
4. : , , .
1. ) :
characteristic, design, drawing, project, step, structure, architect, block, condition, basis, procedure, designer, knowledge
:
basic, long, also, every, next
:
in order to, over, eitheror, according to, each
:
build, consist, depend, function, need, decide, explain.
b) , . , .
2. .
| A characteristic consist of depend upon describe each next basic | B | A manufactured product select knowledge long need drawing condition | B , |
3. :
build builder building
design - designer
1.2
A, B . , .
A
['streŋθ]; ['mIksCq]; [səb'Gekt]; [kLz]; [Ik'sesIv]; ['jHnIt]; [kqm'presIv]; ['pWpqs]; [dI'menSqn]; [InC]; ['Jkwql]; [pq'zISqn]; ['PbGIkt]; [DAs].
B
| denomination excessive thus object v. | unite unit compressive course | purpose strength object n. mixture | subject v. cause dimension subject n. | inch equal possession position |
A
STRENGTH AND STRESS
Part I
All construction materials must resist force. A force has a value and a direction. Gravity causes most of the forces in construction. There are other causes such as wind. Unit stress (stress) is force per unit area over which the force acts. We obtained it by dividing the force by the area on which it acts and show it as pounds per square inch, or psi.
Strength of a material is the ability to resist a force. That ability depends on the size and shape of the object and its material. Strength of a material is equal to the unit stress that the material can resist. Strength has the same units as unit stress.
The useful strength of a material is equal to the unit stress at failure. Failure takes place when an object can not serve its purpose. The material may fail if it breaks or if deformation is excessive. A change in the outside dimensions of an object that a force has caused is deformation.
The amount of deformation depends on the size and shape of the object and its material. When we divide the total change in dimension by the original dimension we obtain unit strain (strain). Unit strain is the result of unit stress.
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We can see unit strain when we stretch a rubber band or compress or twist a piece of rubber hose. A rubber band which we subject to a compressive force becomes much shorter and a little wider. A sample which we subject to a tensile stress becomes much longer and a little narrower.
There are three kinds of unit stresses and corresponding strengths - compressive, tensile, and shear. They depend on the position of the forces which act on the object. The three are shown in Fig. 1.
a b c
(a) Compression (b) Tension (c) Shear
In each case unit stress = P/A
FIGURE 1. Illustration of stresses
Notes:
ability n.
hose n.
pound n. (0,454 )
.
1. What must all construction materials resist?
2. What does a force have?
3. What causes most of the forces in construction?
4. What do we call stress?
5. What is strength of material?
6. What does that ability depend on?
7. What units does strength have?
8. When does failure take place?
9. What does deformation mean?
10. What does the amount of deformation depend on?
11. What is the result of unit stress?
12. How many kinds of unit stresses do you know? What are they?
1. )
:
compression, value, shear, inch, strength, cause, tensile strength, gravity, dimension, force, unit stress, strain, construction, shape, failure, size, unit, tensile stress, deformation, case, tension, amount, position, object, compressive strength, band, direction, weight, shear strength, area, purpose
:
excessive, different, outside, rubber, square, wide, narrow, equal, short, original, total, useful
:
the same, for, such as, if, per, much, also, which, most
:
subject, produce, strengthen, resist, twist, break, mix, obtain, increase, compress, act, fail, weaken, serve, divide, take place, appear, stretch, pull
) ? . , ed.
) ? ? ?
2. :
; , ; ; , ; , ; ; , ; , ; ; , ; ; , ; ; ; ; ; , ; ; ; ; ;
; ; , ; ; , ; , ; (); , ; , ;
; ; , ; , ; ; ;
; ; ; ; ; ; ; .
3. , , ? .
4. . .
| produce direction quantity narrow thus size shear total wide unit compress band | , , , | shape together area failure divide similar cause obtain in order to aggregate gravity available | , , |
5. :
| compression strengthen | some under | similar large | long the same | narrow lose |
1. , there + be.
1. There are three kinds of unit stresses and corresponding strengths compressive, tensile and shearing.
2. There had been a garden here before 2004.
3. There are many building materials in construction.
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4. There wasnt a garden in front of the house.
5. There are many classrooms at school.
6. There are many students at the University.
7. There will be a modern laboratory at our school.
8. There were some schools in our town.
9. There is a cottage.
10. There isnt great amount of deformation in this material.
11. There have been some pictures.
12. There were different projects of this building
2. , .
1. All construction materials must resist force.
2. It cant be determined experimentally.
3. The material may fail by breaking or by excessive deformation.
4. We can see each other every day.
5. The students may use the dictionary.
6. They could use these construction materials in building.
7. The force on a structure may be larger than the force which we designed.
8. Steel may be weakened by rust.
9. There are different forces that a construction material must resist.
10. These students could not speak English last year.
3. :
| long good short many wide | difficult great important little versatile | bad large much small narrow |
4. , .
1. A rubber band becomes much shorter and a little wider.
2. Under tension it becomes much longer and a little narrower.
3. Steel and cement are the most important building materials now.
4. New building materials must function better.
5. It is the worst film that I have seen.
6. The designer describes more characteristics of this material.
7. The shortest way () is sometimes not the best way.
8. It was a less difficult process.
5. , , , :
1. Such a change in the outside dimensions of an object is deformation.
2. They plan to use the results of our work.
3. We subjected a rubber band to a compressive force.
4. The useful strength of a material is equal to the unit stress at failure.
B
There are several reasons why engineers must not design a material which is under the stress near to the failure stress:
1. Failure unit stress may be smaller than the engineers designed.
2. The force on a structure may be larger than the engineers designed.
3. Materials may weaken due to rusting (steel), rotting (wood), or cracking (concrete).
The failure unit stress is greater than the allowable unit stress by the safety factor. If failure unit stress is twice the value of the allowable unit stress, the safety factor is two.
Usually engineers determine failure unit stress experimentally. Designers select kinds of material and sizes and shapes of members which will support loads that subject the member to unit stresses. These unit stresses must be equal to or less than the allowable. Economy requires that the unit stress must be near the allowable; if it is not, the use of the material is not efficient. Engineers call this unit stress - the working unit stress.
There are several important factors that engineers must determine when they decide on a safety factor:
1. How we can calculate loads,
2. How we can calculate unit stresses,
3. How serious the results of a failure are, and
4. How much warning the material gives before it fails.
Notes:
failure stress
experimentally adv.
rotting n.
.
1. Why must a material not be stressed near to the failure stress?
2. What do we call the safety factor?
3. How is failure unit stress determined?
4. Who selects an allowable unit stress?
5. What factors must engineers determine when they decide on a safety factor?
1. there + be. .
2. . .
3. . .
4. : , , .
1. ) :
cracking, load, member, reason, safety, working stress
:
allowable, efficient, here, near, several, twice, usual
:
before, than
:
determine, require, support
b) , . , .
2. .
| A | B allowable support near object outside load several | A | B here small value usual warning deformation member |
3. :
fail - failure
use - useful
1.3
A, B . , .
A
['meÁsqnrÁ]; [haI]; [rI'meIn]; [feIl]; ['xksIql]; ['xkSqn]; [q'laV]; [dI'vaId]; ["pWpqn'dIkjVlq]; ["enGI'nIq]; ['veqrIqs]; ['DeqfL]; [haV'evq]; [pOInt]
B
| remain hover axial divide | perpendicular perpetual engineer however | various therefore hay high | virus point auction masonry | action allow reman fail |
A
STRENGTH AND STRESS
Part II
If a metal bar with a square cross section 2 in. by 2 in. breaks when we pull it with a force of 200,000 lb, its breaking strength is the same as the unit stress or:
Breaking strength = P/A
= 200,000 lb / 2 x 2 sq in.
= 50,000 lb per sq in.
The deformation that we can allow in the bar depends on its use. Therefore, failure depends upon the purpose for which we use the material. Beams which support a roof can withstand any unit stress that does not break them; but if the beams support a plaster ceiling, they fail at a unit stress that causes plaster cracking.
Designers determine the unit stress that can cause failure for various materials and their uses. However, they dont design to stress a material to the point where it will fail. Instead, they select a lower unit stress (the allowable unit stress), and this is the maximum which they allow.
In order to determine unit stress engineers divide the force by the original area upon which it acts. Tensile and compressive unit stresses act on the cross-sectional area perpendicular to the direction of the force. Shear unit stresses act on the cross-sectional area parallel to the direction of the force.
Shear unit stress does not act equally over an area, and the engineer must consider the unit stress at the location of the highest unit stress. The action of shear unit stresses is complex compared to that of the axial unit stresses, tension and compression.
Since forces change the cross sections in size, they influence the unit stresses. If a force remains constant, the actual unit stress changes when the cross section changes. Engineers determine unit stress on the basis of the area as it is before any force acts on it.
Notes:
breaking strength
shear unit stress (),
.
1. What is the breaking strength of the metal bar?
2. How is it determined?
3. What does failure depend upon?
4. What unit stress can beams support?
5. What can happen in the case of a plaster ceiling?
6. Which unit stress do designers determine?
7. What do engineers do in order to determine unit stress?
8. How do tensile and compressive unit stresses act?
9. How do shear unit stresses act?
10. Why do forces influence the unit stresses?
11. What takes place if a force remains constant?
12. How do engineers determine unit stress?
1. )
:
reason, load, location, plaster, action, compression, point, metal, roof, ceiling, member, bar, tension, beam, cross section, direction, area, beam, purpose
:
axial, instead, actual, low, various, parallel, any, compared to, high, complex, therefore, perpendicular, square, the same, allowable, equally, constant
:
by, in order to, that, if, for, as, since, however
:
stress, allow, change, remain, consider, influence, withstand
) ? . , ed.
) ? ? ?
2. :
; ; , ; ; ; ; ; ; ; ; ; ; ; , ; ; ;
; , ; ; ; (); ; ; (); ; , ; , ; ; ; (); ; ;
; ; , ; ; ; , ; ; , ; , ; , ; ; ;
; , ; ; , ; (2);
3. , , ? .
4. .
| twice actual high ceiling reason near various step need low instead allow | therefore plaster several axial due to than consider also condition basic consist roof | - () |
5. :
building
building material
strength
, :
project, calculate, aggregate, stress, layer, masonry, force, binder, block, crushed rock, stretch, unit stress, beam, limestone, wood, column, brick, architect, shear, strain, structure, ceiling, compression, cement, clay, fatigue, design, tension, gravel, hole, failure, drawing, sand, gravity, cracking, safety, withstand, rod, constant, concrete
, .
1. , that.
1. The deformation that can be allowed in the bar depends on what it is used for.
2. Beams can withstand any unit stress that does not break them.
3. The action of shearing unit stresses is complex compared to that of the axial unit stresses.
4. That was an allowable deformation.
5. They know that unit stress causes failure.
6. They used that metal bar with a square cross section.
7. That failure depends upon the material that is used is natural.
8. Beams fail at a unit stress that causes plaster cracking.
9. This material is better than that one.
10. The unit stress that causes failure can be determined for various materials.
2. :
metal bar, square cross section, failure strength, plaster cracking, shear unit stress, construction project, stress change, tension degree, steel invention, iron rod, plaster ceiling problem, brick layer, design procedure, building maintenance.
3. :
862; 6076; 200,000; 373,200; 1,270,480; 12.05.2005; 597; 734; 10,754; 31.12.1998.
4. :
25; 87; 3; 32; 91; 14; 43; 75; 11; 68; 21; 15;
4. the the :
1. The more we learn now the better engineers we will be.
2. The harder (hard ) the problem the more interesting it is to solve ().
3. The sooner (soon ) you come the better.
4. The more careful () engineers are when they design a building the less problems the builders will have in its construction.
5. there + be.
1. Because there is so little deformation, there is no warming.
2. There will be hard problems to solve.
3. There was deformation in the bar.
4. There were beams which could withstand any unit stress.
5. There are beams which support a plaster ceiling.
6. .
1. They could use a material with higher compressive strength
2. The builder must understand construction materials.
3. Each material can function well over a long time.
4. Builders may use different materials.
5. Basic materials must all be described.
B
In the tests which engineers make in order to determine strength they subject a material to a force that increases until the material breaks. These tests take a few minutes. However, in a structure, forces may act for long periods of time, they may act, not act for some time, and act many times, and they may act suddenly with impact or shock.
A material changes slowly when a force acts on it for many years, even though the force is too small and cant cause failure in a short time. This deformation is creep. The creep may result in failure.
Although a force of a certain amount cannot cause failure no matter how long it acts, it can cause failure if it acts and stops acting many times (hundreds of thousands of times) even if it takes place over a shorter time. Application and removal of unit stress to the structural members of a bridge occurs each time a car goes along it. Failure from this cause is fatigue, and it occurs with very little deformation.
Because there is so little deformation, there is no warning and the break is sudden. However, it begins as a crack and becomes larger over many cycles until it fails. The smaller the unit stress, the more times it must occur to cause failure. There is a unit stress below which the material will not fail at any number of cycles. It is the endurance limit.
Notes:
cycle n. ,
endurance limit ,
no matter ,
sudden
thousand n.
.
1. What tests are made to determine strength?
2. What is creep?
3. What do we call fatigue?
4. What do we call the endurance limit?
1. the the . .
2. . .
3. . .
4. : , , .
1. ) :
application, crack, creep, impact, bridge, number, removal
:
structural, too, even, certain, little, few, long, slow
:
below, although, so, until, along, though, because
:
result in, repeat, occur
b) , . , .
2. .
| A | B creep however take place increase time amount application | A | B determine until subject cause occur break so |
3. :
crack - cracking
few little
1.4
A, B . , .
A
[q'bsLb]; ["InsjV'leI¿qn]; ['¾´Åql]; [Ðqn'ËInj³]; ['ËeÅÃrqÀq]; ['laIËweIË]; [Ãq'senË]; [rI'dj³s]; [IÐ'spensIv]; [Tr³]; ['meZ]; ['verI]; ['fbrIÐeIt]; ['pxtn]
B
| through absorb measure vary | pertain insulation temperature thermal | throw radius continue lightweight | percent pattern reduce fabricate | very contain mega expensive |
A
THERMAL CONDUCTIVITY AND SOUND ABSORPTION
A building ought to be warmer than the outside air in cold climates and cooler than the outside air in hot climates. Heat flows to a cooler area like water flows to a lower level. The flow continues until outside and inside temperatures are equal. Heat movement takes place by conduction through any solid object that separates areas of different temperatures. The rate at which the movement of heat takes place varies with the material through which the heat passes. The rate is measured as thermal conductivity (U) of heat (in British thermal units (Btu)) that is transmitted per square foot of cross section per hour per F difference in temperature between the two sides of the material. Insulation, which is material with a very low U, is used in order to make the rate of heat flow as low as possible. The U of a material varies directly with its density. The best insulation, expanded plastic foam, consists of bubbles with the proportion of solid material less than 1 percent of the volume and the rest consists of air or gas. Insulation is also made of other porous material. However, some structural materials also have a low U factor and therefore serve as insulation. Wood and certain types of lightweight concrete are two such materials.
Sound Absorption Loud sound should be avoided in most buildings and has to be reduced by the use of acoustic material which is to absorb it, whether it is produced in the building or outside. Sound is absorbed by air spaces in the material. Porous material is used, or material is fabricated with a pattern of openings so as to be able to absorb sound. Wood and porous concrete are the most effective in sound absorption.
Notes:
bubble n. ,
cool adj.
expanded plastic foam
loud adj.
porous adj.
sound absorption
warm adj.
.
1. What ought a building to be in cold climates and in hot climates?
2. What is the reason for that?
3. What is the cause of heat movement?
4. What does the rate of heat movement depend on?
5. How is the rate of thermal conductivity measured?
6. What is insulation?
7. Why is expanded plastic foam the best insulation?
8. What other materials have good insulation?
9. How should loud sound be reduced?
10. What is sound absorbed by?
11. What materials are the most effective in sound absorption?
1. )
:
lightweight concrete, conduction, space, level, opening, density, movement, sound, percent, foot, heat, pattern, insulation, difference, thermal conductivity, flow, side, temperature
:
solid, outside, effective, acoustic, possible, like, direct, expensive, inside
:
between, whetheror, so as, through
:
transmit, fabricate, continue, separate, absorb, avoid, reduce, measure, vary, pass
) ? . , ed.
) ? ? ?
2. :
; ; , ; ; , ; ; ; , ; ; , ; ; , ; ; ; , ; ; ; ;
, ; ; ; , ; ; ; ; ; ; ; ; ; , ; (); ; , ;
; ; , (2); ; , ; ; , ; ; ; ; , ; ;
, ; , ; , ; , ; ; ; (2); , ; , ; ;
3. , , ? .
4. . .
| degree serve advantage aggregate layer dimension case each other weight sometimes mortar rod | - | compression the same hole for depend number step together impact withstand resist excessive |
5. a) :
outside, cold, increase, give, short
b) :
because, change, divide, fabricate, under
1. , .
1. Loud sound is avoided in most buildings.
2. Unit strain was caused by unit stress.
3. The material will be stressed near to the failure stress.
4. The rate is measured as thermal conductivity of heat.
5. Usually failure unit stress is determined experimentally.
6. This unit stress is called the working unit stress.
7. Sound will be absorbed by air spaces in the material.
8. Unit strain can be shown by stretching a rubber band.
9. Sound must reduced by the used of acoustic material.
10. Important factors are listed here.
11. The loads can be calculated.
12. Insulation was also made of other porous material.
13. That ability depends on the size and shape of the object and the material of which it is made.
14. Unit stress is expressed as pounds per square inch.
2. to be .
1. The engineers are designing a new building now.
2. The building insulation was to be examined ().
3. Steel and cement were introduced in the nineteenth century.
4. Modern cement which was called Portland cement was invented in 1824.
5. Portland cement is a mixture of limestone and clay.
6. Construction materials are to perform under specific conditions of usage.
7. In the basis of all these qualifications is the knowledge of materials.
8. The plans explain briefly what materials are to be used.
9. They were discussing () sound insulation of a house when we came.
10. All basic materials are to be described.
3. , .
1. The designer has to make plans which consist of drawings.
2. This design should be discussed.
3. The designer also explains the characteristics which the materials are to have.
4. Failure takes place when an object is not able to serve its purpose.
5. New insulation materials had to be developed ().
6. In cold climate buildings ought to have thermal insulation.
7. Sound should be avoided in most buildings and has to be reduced by the use of acoustic material.
8. Material is fabricated with a pattern of openings so as to be able to absorb sound.
4. , .
1. He had much more serious problems than we thought ().
2. The thermal insulation of this building is the worst.
3. The unit stress at the location of the highest stress must be considered.
4. It will be easier to calculate the load if we use this method.
5. The material which was selected is the best.
6. The smaller the unit stress, the more times it must be repeated to cause failure.
5. , that.
1. Heat flows to an area that is cooler.
2. That the sound insulation of the house was bad was to be considered.
3. That is the design that we are to discuss.
4. Those tests were made by the engineers.
5. We know that concrete is a mixture of cement, sand, aggregate and water.
6. Beams that support a roof can be made of steel, concrete or wood.
6. :
heat movement, movement rate, material density, sound absorption, air spaces, creep deformation, stress location, failure cause, sound insulation, construction material.
B
The most important properties of building materials are their cost, their mechanical properties, which include their weight, their thermal and acoustic properties, their durability and their resistance to fire. Other important properties which are connected with the basic properties of the material are the ease of manufacture of the material, the corrosion and chemical resistance and the texture and appearance of the material.
Building materials may be divided into natural and artificial. The examples of natural building materials are wood, sand, clay. The examples of artificial building materials are cement, concrete, brick. The most important mechanical properties of building materials are their weight, tensile strength, shear strength, compressive strength, fatigue resistance, elasticity and creep under load. Other important mechanical properties are their strain capacity and their resistance to rain and moisture. All these properties of materials are based on those values which are given by standard tests and, in many cases the full details of the test ought to be known in order to assess the material. Some properties, for example the compressive strength of concrete, depend on the way the test is done and are based on other general properties.
Notes:
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1. What are the most important properties of building materials?
2. Are there any other important properties of building materials? What are they?
3. What are the two types of building materials?
4. What are the examples of each type?
5. What are the important mechanical properties of building materials?
6. What values are they based on?
7. Does the way the test is done influence any properties?
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| A | B property these fatigue fire standard brick some | A | B artificial shear strength clay corrosion ease their depend on |
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