III. Перекладіть наступні складові слова українською.

hold-up, whatsoever, however, to overcome, to withstand, to underlie, within, cross-section.

IV. Перекладіть наступні словосполучення, у складі яких є складові слова.

slab-type roadway, slab-type pavement, cross-sectional area, high-tensile steel, frost-susceptible soil.

V. Перекладіть слова, які утворені за способом конверсії.

crack- to crack, design - to design, form - to form, compound -to compound, joint - to joint, water - to water, size - to size, increase - to increase, place - to place, cost - to cost, repair - to repair, result - to result, surface - to surface.

VI. Перекладіть слова грецького походження українською.

type, critical, practice, method, analysis (pl. analyses).

VII. Перекладіть слова латинського походження українською.

position, material, form, adequate, minimum (pl. minimal), to minimize, formula (pl. formulae), to utilize, to induce, to calculate, coefficient, distance, effective, uniformly, to combine, function, to limit, approximately, modulus, (module), elasticity, location.

VIII. Дайте українські еквіваленти наступних сполучень іменників.

concrete slab, concrete road, concrete pavement, surface appearance, tensile stress, tie bar, road design practice, wire mesh, road construction, elongation properties, strength properties, crack control, road experience, design load.

IX. Складіть англо-українські пари словосполучень, еквівалентних за значенням.

1. sealing compound; 2. to pay attention; 3. supporting soil; 4. to overcome friction; 5. to withstand the stresses; 6. amount of longitudinal steel; 7. area of steal; 8. free joints; 9. allowable working stress; 10. amount of transverse steel; 11. welded wire mesh; 12. reinforced concrete road construction; 13. induced stress; 14. flexural stress; 15. reinforced crack; 16. reinforcing steel; 17. continuous reinforcement; 18.transverse joint; 19. frost-resisting soil; 20. frost-susceptible soil; 21. structural capacity; 22. continuously reinforced concrete pavement; 23. heavily travelled road.

1. поперечний шов; 2. морозостійкий ґрунт; 3. сталева арматура; 4. безперервне армування; 5. ґрунт, схильний до замерзання; 6. тріщина, яка утворилася при армуванні; 7. структурна міцність; 8. безперервно армоване бетонне дорожнє покриття; 9. будівництво залізобетонної дороги; 10. напруження, яке спричинено іншим напруженням; 11. складне напруження; 12. напруження при вигині, згинальне напруження; 13. дорога з інтенсивним рухом; дорога з великим вантажонапруженням; 14. величина площі перерізу поперечної арматури; 15. зварена дротяна сітка; 16. припустиме робоче напруження; 17. звертати увагу; 18. ізоляційна суміш; 19. несущий ґрунт; 20. витримувати напруження; 21. долати тертя; 22. шви без арматури; 23. величина площі перерізу поздовжньої арматури; 24. площа перерізу арматури чи сталевого елементу.

AMOUNT, TYPE AND POSITION OF REINFORCEMENT

Even when an unreinforced concrete slab is placed on an excellent foundation it can be expected to crack. If the slab is well designed and constructed, these cracks will only be of the 'hairline' variety, and so are of no dangerous consequence whatsoever. If, however, say, the joints between slabs are too far apart, then the cracks may be larger and more numerous so that foreign material can enter them and water can percolate easily to the subgrade. If traffic is heavy the broken edges may become spalled, so that the cracks become wider and eventually the pavement fails. Early maintenance in the form of cleaning out the cracks and then filling them with a plastic sealing compound can, of course, prevent too great a deterioration taking place. This however is very expensive - not only because of the cost of the actual repairs but also due to the cost of hold-ups to traffic - and it also results in an unsightly surface appearance about which the general public are likely to be very critical.

If adequate attention is paid to the 'reinforcing' of the top of a slab, not only will many of these cracks be prevented from starting - at least in the early life of the slab - but also those cracks which do start will be prevented from opening, and spalling and the ingress of water and foreign matter is minimized. The extent to which this is done is dependent on the amount and type of reinforcing steel utilized.

As has been described before, the supporting soil resists the movement of a concrete slab when it contracts and so tensile stresses are induced in the slab. The maximum tension at any point in the slab is equal to the force required to overcome friction between the slab and the soil from that point to the nearest edge or free joints, i.e. one that has no tie bars or bonded reinforcement across it. This tensile stress is greatest at the middle of the slab and so the steel is usually designed to withstand the stresses at this location.

Experience has shown that small bars or mesh are more effective reinforcing agents than the same area of larger bars since they can be distributed more uniformly in a concrete slab. This combined with the fact that higher working stresses can be used with welded wire mesh, has resulted in this material being the most widely used form of steel in reinforced concrete road construction.

As has been stated the primary function of the steel is to limit the maximum width of crack that may develop and only incidentally it is expected to resist the induced flexural stresses. This means that the width of a reinforced crack is dependent on the elongation properties of the steel and not on its strength properties. Since both mild and high-tensile steel have approximately the same modulus of elasticity, it follows that the choice of steel to be used for crack control can be considered to be independent of the grade of steel utilized.

Since reinforcing steel is not designed to act in flexure, its exact location within the slab is not particularly important as long as it is well bonded to the concrete and adequately protected from corrosion. The most common practice is to place it about 2 in. below the final surface.

Завдання I. Знайдіть в тексті речення, яке містить незалежний дієприкметний зворот. Відповідну частину речення перекладіть українською.

Завдання П. Знайдіть в тексті речення, які містять суб’єктний інфінітивний зворот та перекладіть їх українською.

CONTINUOUS REINFORCEMENT

Concrete roads can also be built with no transverse joints if sufficient reinforcing steel is employed in their design. Roads which are so constructed and which contain enough steel to keep closed the many more cracks that can be expected are said to have continuously reinforced pavements. Experience to date has indicated that minute cracks occur more frequently in continuously reinforced pavements than in normally reinforced slab-type roadways. In fact the greater the amount of steel used the closer the distance between cracks. In this case, however, because of the large amount of steel, which is used, the cracks remain intact and do not increase in size. If too little steel is used the cracks will be formed farther apart but they are liable to widen.

Road experience indicates that the amount of steel used in continuously reinforced pavements must be such that its cross-sectional area is greater than about 0,6 per cent of the concrete cross-section before the advantages of continuity can be experienced. These advantages include low crack maintenance, the elimination of 'pumping' of frost-susceptible soils and an increase in structural capacity. While the extra structural capacity definitely permits thinner pavements to be used for a given design load, there is yet no exact method of analysis available which makes it possible to say how much a reduction may be in any particular instance.

Continuously reinforced concrete pavements cost more to construct, as well as requiring more steel, than normally reinforced slab- type pavements. Thus their usage at this time is generally limited to very heavily travelled roadways on which it is desired to keep traffic delays to minimum.

Завдання I. Дайте відповідь на запитання:

1. Які переваги має безперервно армоване покриття? 2. У яких випадках використовуються безперервно армовані покриття?

Lesson 11

Exercises

I. а) Вкажіть суфікс в наступних словах.

б) Визначте частину мови, до основи якої додано суфікс.

в) Поясніть, яке значення даний суфікс надає основі слова.

г) Перекладіть слова українською:

1) prestressing, loading, stretching, casting, saving;

2) precaution, condition, application, discussion, reduction, compression, exception, section, expansion, pretension;

3) strength, length, width, depth;

4) abutment, pavement, development, reinforcement;

5) quality, difficulty, safety;

6) moisture, temperature, structure;

7) to associate, to locate, to incorporate, to separate;

8) to classify, to qualify, to simplify;

9) constructional, normal, principal, initial, vertical;

10) allowable, liable, available, comparable, suitable;

11) continuous, previous;

12) compressive, expensive;

13) readily, fairly, especially, relatively, freely, economically, subsequently, essentially, satisfactorily.

II. а) Вкажіть префікс в наступних словах.

б) Поясніть, яке значення даний префікс надає основі слова.

в) Перекладіть слова українською.

reinforcement, disadvantage, pretension, post-tension, prestress.

III. Перекладіть групи слів одного кореня українською.

1. force /n/ - to force - forced /a/ - forcedly - forceful - forceless - to reinforce - reinforcement;

2. compress /n/ - to compress - compressed /a/ - compressibility - compressible - compression - compressor.