Пособия / Л.П. Даниленко, Ю.Ю. Сильман TECHNICAL ENGLISH FOR CIVIL ENGINEERS AND STRUCTURAL DESIGNERS
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The material of a roof may range from banana leaves, wheaten straw (солома) or sea grass to laminated glass, copper, aluminium sheeting and precast concrete. In many parts of the world ceramic tiles have been the predominant roofing material for centuries.
The construction of a roof is determined by its method of support and whether the roof is pitched or not. The pitch (скат, уклон) is the angle at which the roof rises from its lowest to highest point. Most domestic architecture, except in very dry regions, has sloped, or pitched roofs. Although modern construction elements such as drainpipes may remove the need for pitch; roofs are pitched for reasons of tradition and aesthetics. So a pitch partly depends upon stylistic factors, and is partially connected with practical function.
Some types of roofing, for example thatch roof (тростниковая крыша), require a steep (крутой) pitch in order to be waterproof and durable. Other types of roofing, e.g. pantile roof (кровля из желобчатой или голландской черепицы), are unstable on a steeply pitched roof but provide excellent weather protection at a relatively low angle.
Pantile roof |
Pantile roof |
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In regions where there is little rain, a flat roof with a slight runoff (сток) provides adequate protection against an occasional heavy rain (ливень). Drainpipes also remove the need for a sloping roof.
The durability of a roof is a matter of concern because the roof is often the least accessible part of a building for repair and renewal, while its damage or destruction can have serious effects.
Parts of a roof
There are two parts of a roof: its supporting structure and its outer skin (внешний слой/обшивка) or upper weatherproof layer. In some buildings the outer layer is also a self-supporting structure. The roof structure is generally supported upon walls.
Roof Styles
Throughout the history and especially throughout the past couple of hundred years the styles of roofs vary from area to area. There are different designs, styles and shapes of roofs. They should correspond to structure to be covered. Some of the most primary needs that a structure demands from a roof are protection from the weather, general design suitability with the existing structure, and placing the internal elements such as piping, electrical wiring, ventilation, insulation.
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Task. Read the text and give a short summary of it.
TEXT 13. SHAPE OF ROOFS
Shape of roofs differs greatly from region to region. The main factors which influence the shape of roofs are the climate and the materials available for roof structure and the outer covering.
The basic shapes of roofs are flat (плоская), gable (двускатная), hip or hipped (четырехскатная), arched (арочная) and domed (купольная). There are many variations of these types. Roofs constructed of flat sections that are sloped are referred to as pitched roofs (скатные крыши), generally, if the angle exceeds 10 degrees. Pitched roofs, including gabled and hipped roofs, make up the greatest number of domestic roofs. Some roofs follow organic shapes, either by architectural design or because of a flexible material used in the construction.
Illustrations of common roof shapes
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Flat roof |
Shed roof |
Pitched roof |
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Gable or saddle roof |
Tented or pavilion roof |
Gambrel roof |
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Hip (hipped) roof |
Half-hip roof |
Saw-tooth roof |
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Rhombic roof |
Rainbow roof |
Barrel roof |
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Conical roof |
Spire |
Onion dome |
Welsh spire |
Flat Roof.
Flat roofs are common especially for commercial buildings. Flat roofs are definitely the simplest roofs to build because they have a little pitch. Waterproofingis very important forflat roofs.
Shed Roof (односкатная крыша).
A shed roof is basically a flat roof but has more pitch. It is frequently used for additions on houses.
Gable Roof (двускатная крыша).
Gable roof design is one of the more simple styles of roofs. The gable roof style looks like an inverted /upside down V. Gable roofs are not ideal for areas with high wind because they can easily catch the wind like a sail would. Gabled roofs also offer larger space for an attic.
Hip (hipped) Roof (четырехскатная, вальмовая или шатровая крыша) is a widespread and popular type of roof. It
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creates a solid and attractive profile when combined with a low and stretched structure. A hipped roof has four sides and a gentle slope. Hipped roofs are a common residential style roof. This type of roof is more difficult to construct when compared to flat and gable roofs because it has a more complicated truss and rafter (стропила) structure. Hipped roofs can be both square and rectangular.
Half-Hipped Roof (полувальмовая крыша)
Mansard Roof (мансардная крыша).
A mansard roof is a French design and is more difficult to construct than the hipped or gable roof. A mansard roof is a “historic” variation of a hipped roof. These types of roofs are unusual, but offer plenty of interior space for an attic.
A-Frame Roof (крыша А-образной формы):
This type of roof is very popular for churches, cottages, homes, and other structures. The roof acts as both the roof and the walls for a structure.
Shed roof (шедовая крыша). A shed roof is similar to a flat roof, but uses a steeper pitch which allows for better drainage. Shed roofsofferlotsofdesign options.
Arched roof (арочная крыша). Arched roofs offer excellent structural strength, an unusual and eye-catching design. Nowadays, arched roofs are typically made of curved steel.
Domed roof (купольная крыша). Circular roofs can take many shapes – either flat or pitched, or even domed. Domed roofs are strong, unusual and may be expensive and complicated to construct.
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Saw-tooth roof (пильчатая крыша).
Saw-tooth roofs were traditionally an industrial/warehouse type of roof. They are now increasingly popular in houses, thanks to the amount of daylight they allow.
Curved roof (криволинейная крыша).
Curved roofs, most commonly made of steel in modern designs, offer the opportunity to add organic curves and a softer, rounder look to the house.
Task. Translate the text using the dictionary at the end of the book.
TEXT 14. ROOF MATERIALS
The choice of material is an important aspect in roof construction. Some materials are more common in certain areas and some materials are ideal for different types of roof pitches/slopes while others are not good for definite roof slopes. The three main roof slopes that determine the material used are flat roofs (no slope or a very slight slope), low slope, and steep slope (крутой наклон).
The most widely used materials for roof construction.
Asphalt Shingles (битумная кровельная плитка) are the most common steep-slope residential roofing material used for roofs. Asphalt shingles vary in quality and price.
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Metal
Metal is a very common material used for roofs. There are many different types of metal roofing (металлическая кровля) systems. The types of used metal vary from zinc to steel, copper, aluminium, and tin.
Tile (черепица):
Tile is one of the most expensive materials used for roofs. Although the traditional clay tile is probably the most well known tile material it is not the only one. Other materials that are used to create tile products are metal, concrete, slate (шифер), and various synthetic compositions.
In the recent past steep-sloped residential roofing selection was relatively simple: the choice was between asphalt shingles, cedar shingles (доска обшивки из кедра), clay and possibly concrete roofing tiles, or, rarely slate. Today, these basic choices are available, but these materials have developed considerably, particularly laminated asphalt shingles, new tile shapes and colours, and new protective shingles treatment. In addition, a whole new set of materials has come into use including metal shingles, tiles, fiber-cement and plastic profiles that imitate wood and slate. Low-slope roofing systems have also developed with the increased use of modified bitumen membranes (покрытие строительным битумом) and singleply roofing (однослойное кровельное покрытие) systems.
Roofing tile is differentiated by its shape and composition. Its other important characteristics are breaking strength, absorption or porosity, resistance to freeze-thaw, joining methods, and installation details. The porosity of roof tiles is very important
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in climate with a repetitive freeze-thaw cycle. The more porous a roof tile is, the more water it will absorb. Water that freezes in a roof tile can causethe material crack.
The roof installation method should be based upon roof slope, type of roof deck, climate, seismic considerations, local building codes, and manufacturer’s recommendations.
Task. Scanthe texttogetthefullidea ofit.
TEXT 15. SHELL ROOF
(покрытие или крыша в виде свода-оболочки)
A shell roof is a common type of a roof that is made from thin material. The roof is curved and it is used to cover large, onestorey buildings. As it is usually aesthetically pleasing, a shell roof is commonly used in public buildings. Shell roofs are useful when the inside of the building is open and does not contain walls or pillars that could support a flat or pitched roof. The shell roofs are especially advantageous in industrial and civil buildings where large unoccupied areas of about 30×30 m or more are to be roofed over without intermediate supports. Shell roofs economize materials and have a smaller self-weight in comparison with roofs made of such structures as roof slabs, trusses, beams, arches and secondary roof trusses. Shell roofs are expensive architecturally. Thin shell roofs are commonly cast in-situ.
The floor space under a shell roof can be made much larger than the floor space below another type of roof. This is because
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the curve in the roof adds additional structural support, allowing the roof to be heavier and larger. It is an ideal roof structure for office buildings and public buildings, such as libraries, theaters and recreation centers.
These roofs have interesting aesthetics and can be used to beautify a building. The Sydney Opera House in Australia is the most famous example of a building with a shell roof.
SydneyOpera House
It is good practice to use prestressed structures in shell roofs. Shell areas subjected to biaxial (двуосное) compression should be checked for stability, cracking-resistance under loads, and also for strength. Prefabricated members should be checked for strength under loads at manufacturing and transporting.
Though the shell roofs have many advantages, they are quite costly to build. The slope of the roof and the curve of the arch must be carefully designed to keep the building stable. A shell roof does not work well on buildings with many levels, as the entire structure of the roof must be built on a single level.
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