Виды фундаментов, применяемые в строительстве
Без сооружения фундамента невозможно возведение кирпичных и железобетонных конструкций промышленного либо коммерческого назначения, а также строительство деревянных домов, коттеджей и высотных жилых домов. В каждом конкретном случае используется определенный вид основания.
Ленточные основания предназначены для кирпичных, каменных, бетонных сооружений, а также деревянных домов, которые планируется облицевать кирпичом. Такой фундамент охватывает весь периметр здания. Может быть как четкой прямоугольной формы, так и неправильной трапециевидной или ступенчатой. Ленточные фундаменты тяжеловесны и массивны. Они требуют большого вложения средств, но просты в изготовлении и надежны, поэтому получили большое распространение.
Столбчатые конструкции используются при строительстве зданий, имеющих каркасные или щитовые стены, а также для возведения облегченных конструкций. В грунт под все углы и пересечения стен устанавливается арматура, различные сваи, после чего между ними заливается цементная смесь. Специальная песчаная подушка либо каменная плита способствуют усилению фундамента. Столбчатые конструкции отличаются более низкой стоимостью, а их изготовление не столь трудоемко. Такие фундаменты часто находят применение в зонах, где в зимнее время наблюдается промерзание почвы. Но следует заметить, что столбчатые основания менее устойчивы, чем ленточные, особенно в условиях, когда грунт не стабилен либо является слабонесущим.
В тех районах, где имеются плавающие грунты либо высокое залегание грунтовых вод, применяются сплошные конструкции. Они представляют собой монолитные плиты или специальные решетки из железобетона. Такие фундаменты герметичны, просты, жестки, но при этом стоят дорого.
20 Read the passages from Builder’s Foundation Handbook (by John Carmody, Jeffrey Christian, Kenneth Labs), find additional information to each point given in bold and discuss them:
The foundation of a house is a somewhat invisible and sometimes ignored component of the building. Good foundation design and construction practice means not only insulating to save energy, but also providing effective structural design as well as moisture, termite, and radon control techniques where appropriate.
Factors affecting the choice of foundation type and construction system include site conditions, overall building design, the climate, and local market preferences as well as construction costs. These factors are discussed below.
Site Conditions.The topography, water table location, presence of radon, soil type, and depth of bedrock can all affect the choice of a foundation type.
Overall Building Design.The foundation type and construction system are chosen in part because of appearance factors. Although it is not usually a major aesthetic element, the foundation at the base of a building can be raised above the ground plane, so the foundation wall materials can affect the overall appearance. A building with a slab-on-grade foundation has little visible foundation; however, the foundation wall of a crawl space or basement can vary considerably from almost no exposure to full exposure above grade.
Climate.The preference of foundation type varies with climatic region, although examples of most types can generally be found in any given region. One of the principal factors behind foundation preference is the impact of frost depth on foundation design. In a southern climate the incremental first cost of creating a basement is greater when compared with a slab-on-grade with no significant required footing depth. Buildings with very shallow foundations can be used in cold climates if they are insulated properly.
Local Market Preferences and Construction Costs.The foundation type and construction system are also chosen based on cost and market factors that vary regionally or even locally. These costs reflect local material and labor costs as well as the availability of certain materials and the preferences of local contractors. More subjective factors that influence a designer’s choice of foundation type and construction system are the expectations and preferences of individual clients and the home-buying public. These more subjective market factors and regional preferences tend to increase the availability of materials and contractors for the preferred systems, which in turn makes these systems more cost-effective choices.
21 Topics for projects and presentations:
1. Shallow foundations.
2. Deep foundations.
3. Fundex piles.
4. Socket-type foundation.
5. Modern tendencies in foundation laying.
“A good designer isn’t afraid to throw away a good idea.
Being process-oriented, not product-driven, is the most important and difficult skill for a designer to develop.”
Matthew Frederick (architect)
Unit 9
| ROOFS |
Figure 9.1 Pitched Roof Structure
1 Match the columns to remember some technical words for parts of a roof. Figure 9.1 may help you:
| 1. covering | a) a thin timber board that is fixed to the end of rafters or roof joints to support the gutters |
| 2. eaves | b) a short rafter that spans the hip and eaves or valley and ridge |
| 3. fall | c) the horizontal board that can be fixed to finish the roof structure at the eaves |
| 4. fascia | d) it can be: a) a horizontal timber member that provides support to the rafters; b) a timber member spanning between roof trusses that supports roof sheets |
| 5. hip | e) the horizontal distance between the supports of structural members such as the rafters |
| 6. jack rafter | f) the timber member fixed to the top of a wall to secure a flat roof joist or rafter |
| 7. pitch | g) the timber member that spans from the eaves to the ridge in a pitched roof |
| 8. purlin | h) a timber at the apex of the roof that takes the tops of the rafters |
| 9. rafter | i) the bottom end of the roof where it meets the wall |
| 10. ridge | j) the point where two inclined roof surfaces meet over an internal angle |
| 11. ridge tile | k) the external material that is laid over the roof structure to protect the inside of the building |
| 12. soffit | l) the edge of a roof that meets a gable wall |
| 13. span | m) a tile that caps the top of the roof |
| 14. valley | n) the angle formed by the slope of the roof |
| 15. verge | o) the slope required on flat roofs for water run-off |
| 16. wall plate | p) the point where two inclined roof surfaces meet over an external angle |
2 a) What types of roofs do you know? Use English-English dictionaries.
b) Look at the pictures. What roof would you prefer for your house? Explain your choice in 3-5 sentences:
 |  |
a) Cross Gabled Roof b) Arched Roof
 |  |
c) Mansard Roof d) Pyramid Roof
3 Discuss the following:
| Rain does not fall on the roof alone. (Proverb) |
| “Compromise makes a good umbrella but a poor roof.” (James Russell Lowell) |
• Write a paraphrase.• Say whether you agree or not, and why.
| READING |
4 a) Transcribe the following words:
retain, ensure, weighted, storage, triangular, require, joists, corrugated, securely.