Пособия / Л.П. Даниленко, Ю.Ю. Сильман TECHNICAL ENGLISH FOR CIVIL ENGINEERS AND STRUCTURAL DESIGNERS

The floor system generally serves two purposes.

Primarily the floor carries vertical dead and imposed load* and transmits these loads through beams to the columns/walls.

The floor also has to act as a horizontal diaphragm that ties the building together, stabilizes the walls and columns, and transmits horizontal wind load to rigid frames or shear walls.

The aims in design of the floor system are:

to deliver the main vertical loads safely by the most direct and efficient route to the columns/walls without excessive deflection or vibration;

to have the necessary horizontal strength/rigidity;

to achieve a homogeneous arrangement and spacing of beams, that will reduce costs;

to accommodate necessary services while constructing – this reduces overall building costs;

to have adequate resistance to or protection against fire for all components.

The layout of the floor depends on the shape and structural system used for a building. In steel-framed structures the column defines the flooring divisions. Primary beams* are put between the columns and may form the part of the main vertical structural frames. As to spans, secondary beams* may be provided to subdivide the intercolumn areas. Column spacing* normally varies from 4 to 8 m. in rectangular-shaped buildings and it can be much greater. Secondary beams are normally spaced at 3 to 4 m.

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Notes:

imposed load – приложенная/временная нагрузка

to accommodate necessary service – размещать необходимые коммуникации

column spacing – расстояние между колоннами primary beam – первичная балка

secondary beam – промежуточнаяиливторостепеннаябалка

Task. Read and translate the text using the dictionary.

TEXT 8a. BASIC FLOOR TYPES

Intermediate floor (типовое/междуэтажное перекрытие)

Basement floor (надподвальное перекрытие)

The attic floor (чердачное перекрытие)

Intermediate floor separates residential floors from each other. Intermediate floor is an important choice of the floor structure. You may need extra load-bearing walls or pillars under the ceiling for reducing the span or the load. The most important requirement is also soundproofing. Waterproofing is sometimes also needed.

Floorings are subdivided into:

ribbed flooring;

precast flooring;

the monolithic reinforced-concrete flooring;

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precast-monolithic flooring;

caisson flooring (кессонное перекрытие).

Types of flooring

Types of floorings widely applied now are the following:

prefabricated panels;

prefabricated reinforced concrete beams, metal and wood beams;

monolithic reinforced concrete, precast-monolithic slabs.

Materials for flooring

The flooring may be of stone, brick, reinforced concrete. Wooden floorings are seldom used now and basically when erecting single-storey buildings. Reinforced-concrete floorings are widely used in the form of precast structures, monolithic and precast-monolithicones.

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Requirements to flooring

Flooring designs should meet the following standard requirements: durability, fire resistance, sound insulation and thermal protection. Protection against moisture penetrating into internal designs of flooring in damp premises (lavatories) is provided with embedding of a special waterproofing layer.

EXERCISES

Ex.1. Answer the questions to the text.

1.What is flooring?

2.Are floors considered to be load-bearing structures?

3.What are the functions of floors in a building?

4.What does the layout of the floor framing depend on?

5.How can floor types be classified?

6.What building materials are used for flooring?

7.What are the main requirements of flooring?

Ex. 2. Choose the correct variant to complete the following sentences.

1.Flooring is

a)verticalexternalprotective design ofabuilding

b)ahorizontalinternalprotectivedesign of abuilding

2.Floors protect all the components of a building from

a)fire

b)rain

3.To subdivide the inter-column areas, builders use

a)primary beams

b)secondary beams

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4.The attic floor is the space between

a)the last storey and the roof

b)the basement and the first storey

5.One of the most important requirements for floors is

a)soundproofing

b)waterproofing

6.The layout of the floor depends on

a)the shape and structural system used for a building

b)homogeneous arrangement and spacing of beams, that will reduce costs

7.Wooden floorings are suitable for

a)single-storey buildings

b)high-rise building

Task. Look through the text and give a short summary.

TEXT 9. EXTERIOR WALLS

Typical exterior walls have one face to outside the house (exterior elements) and one face to inside the house. Not all exterior walls are load bearing, but in most cases they serve as a definite structural function like supporting the roof. There are different types of exterior walls and they are assembled using various construction methods.

Load-bearing walls and columns of a house transfer in turn live and dead loads from the roof to the foundation, which in its turn transfers these loads to the ground. Resistance is also needed to lateral forces from wind and seismic occurrences, which can

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cause deformation and displace buildings from their foundations. These loads are taken into account in the design of buildings.

Designs of exterior walls of civil and industrial buildings are classified according to: static function, material used, the constructive decision.

1.Static function

a)bearing walls;

b)self-bearing walls;

c)not bearing walls.

Bearing external walls take a dead load and loads from adjacent structures of a building (floorings, parting (смежные) walls, roofs, etc.) and transfer them to the foundations. At the same time they carry out bearing and protective functions.

Self-bearing external walls take a vertical load only from a dead load (including load from balconies, bay windows (эркер), and other wall elements) and transfer them to the foundations through intermediate supporting structures and simultaneously they carry out bearing and protective functions.

Not bearing external walls on each floor (or through some floors) rest on adjacent supporting structures of a building – floorings, a frame or walls. Thus, these walls carry out only protective function.

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Bearing and not bearing external walls are applied in buildings with any number of floors. Self-bearing walls rest on their own foundations; their height is limited because of possible mutual deformation of external walls and internal structures of a building. The higher the building, the more difference in vertical deformation, therefore, in panel houses self-bearing walls are applied at height of a building no more than 5 floors.

2. Material used:

stone walls are made of brick (clay or silicate) or stone being the oldest, long-lasting, and most universal materials. They are applied in buildings with any number of floors. Brick is a predominant building material because of its low maintenance, non-combustibility, availability, moisture resistance, and aesthetic appearance. Stone blocks are made of a natural stone (limestone, a tuff (туф), etc.) or artificial materials (concrete, a lightweight-aggregate concrete–бетон налегких заполнителях).

concrete walls are made of the concrete of high specific weight of class В15 and higher, or the lightweight-aggregate concrete of classes В5 ÷ В15. When erecting not bearing external walls the foam concrete, the porous concrete class В2 ÷ В5 are also used. Concrete walls are applied in buildings with any number of floors.

wooden walls are applied in low-rise buildings. For their erection pine timbers in diameter 180 ÷ 240 mm or bars with cross-section 150×150 mm or 180×180 mm, as well as board or plywood (фанера) panels with thickness of 150 ÷ 200 mm are used.

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3.The constructive decision:

a)single layer walls;

b)two-layer walls;

c)three-layer walls.

The quantity of layers of external walls in a building is defined by the results of thermo-technical calculation. In order to meet modern standards on a heat preserving it is necessary in the majority of regions of Russia to project three-layer structures of external walls with an effective heater.

EXERCISES

Ex. 1. Give the English for:

Внешняя стена, несущая стена, смежная стена, пенобетон, фанера, внутренняя обшивка, различные методы сборки, универсальный, долговечный строительный материал, передавать нагрузку на фундамент, вызывать деформацию и смещение здания с фундамента.

Ex. 2. Give the Russian for:

Live load, dead load, flooring, a concrete wall, a wooden wall, a single-storey building, a low rise building, for a building with any number of floors, moisture resistance, to support a roof, a noncombustible material.

Ex. 3. Find the correct answers for these questions.

1. Are all exterior walls considered to be load bearing?

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2.What are the major factors to be considered when designing exterior walls?

3.What does static function include?

4.How is stability of self-bearing external walls provided?

5.What building materials are usually used for exterior walls?

6.How is thequantityoflayersinexternalwallsdefined?

7.How many layers should be applied for the best effect of heat resistance?

Task. Look through the text and tell about wall insulation.

TEXT 10. AN EXTERNAL WALL INSULATION

An external wall insulation system is a thermally insulated, protective, decorative exterior cladding (облицовка, покрытие) procedure involving the use of expanded polystyrene (полистирол), mineral wool (силиконовая шерсть, шлаковата), polyurethane foam (пенополиуритан) or polystyrene foam (пенополистирол), topped off with reinforced cement, mineral or synthetic finish and plaster (штукатурка).

The thickness of thermal insulation depends on the type required in order to create a partition with a heat transmission factor. When calculating the actual insulation requirements, consideration must be given to current Building Regulation Standards. Consideration must also be given to possible risks. Special attention is paid to concrete beams or lintels

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(перемычки) which act as thermal bridges (тепловой мостик) being poor insulation.

External wall insulation systems generally comprise:

an insulation layer (an element which helps to achieve the requisite thermal performance);

a protected weatherproof finish (usually a render – штукатурка), although tiles, and decorative boards can also be used. Insulating render can also be an advantage in certain locations.

EXERCISES

Ex. 1. Match Russian and English equivalents.

Ex. 2. Complete the following sentences. Try to do it without consulting the text.

1. An external wall insulation system is…

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