Types of construction projects

In general, there are two types of construction:

-Building construction

-Industrial construction

Each type of construction project requires a unique team to plan, design, construct and maintain the project.

Building construction

Building construction is the process of adding structure to real property. The vast majority of building construction projects are small renovations, such as addition of a room, or renovation of a bathroom. Often, the owner of the property acts as laborer, paymaster, and design team for the entire project. However, all building construction projects include some elements in common - design, financial, estimating and legal considerations. Many projects of varying sizes reach undesirable end results, such as structural collapse, cost overruns, and/or litigation reason, those with experience in the field make detailed plans and maintain careful oversight during the project to ensure a positive outcome.

Commercial building construction is procured privately or publicly utilizing various delivery methodologies, including cost estimating, hard bid, negotiated price, traditional, management contracting, construction management-at-risk, design & build and design-build bridging.

Residential construction practices, technologies, and resources must conform to local building authority regulations and codes of practice. Materials readily available in the area generally dictate the construction materials used (e.g. brick versus stone, versus timber). Cost of construction on a per square meter (or per square foot) basis for houses can vary dramatically based on site conditions, local regulations, economies of scale (custom designed homes are always more expensive to build) and the availability of skilled tradespeople. As residential (as well as all other types of construction) can generate a lot of waste, careful planning again is needed here.

Industrial construction

Industrial construction, though a relatively small part of the entire construction industry, is a very important component. Owners of these projects are usually large, for-profit, industrial corporations. These corporations can be found in such industries as Infrastructure, Power Transmission & Distribution, metallurgical and material handling, medicine, petroleum, chemical, power generation, manufacturing etc. Processes in these industries require highly specialized expertise in planning, cost estimating, design, and construction. As in building and heavy/highway construction, this type of construction requires a team of individuals to ensure a successful project often undertaken by big construction companies. In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking. Normally, the job is managed by a project manager, and supervised by a construction manager, design engineer, construction engineer or project architect.

For the successful execution of a project, effective planning is essential, involved with the design and execution of the infrastructure in question must consider the environmental impact of the job, the successful scheduling, budgeting, construction site safety, availability of building materials, logistics, inconvenience to the public caused by construction delays and bidding, etc.

Activity 4.2 Questions:

1. What are the types of construction?

2. Which common elements include all construction projects?

3. What undesirable results can be achieved by designing?

4. Who usually is the owner of the industrial projects?

5. Who controls the operation of the design?

Самостоятельное занятие 5

RAILWAY CONSTRUCTION

Activity 5.1Read and translate the text. Try to understand it and be ready to answer the questions.

Railway Construction

Vocabulary

accumulation capacity – способность аккумуляции

accumulation of cold – аккумуляция холода

accumulator – аккумулятор

accumulator at constant level – аккумулятор с постоянным уровнем

computer storage buffer – связь c внешней и внутренней памяти компьютера

computer subroutine – компьютерная подпрограмма

entrain – увлекать

entrained liquid – унесенная жидкость/

entrainment – 1. унос т 2. поток т, эжектируемый струей

entrainment ratio – степень эжекции

entrance side – подводящая сторона

entrance velocity – входная скорость

entropy – энтропия

entry loss – потери на входе

enumeration of bacteria – подсчет бактерий

envelope – 1. покрытие 2. обмуровка

environment – окружающая среда

environment pollution – загрязнение окружающей среды

environmental chamber – климатическая камера

environmental conditions – окружающие условия

environmental cooperation – сотрудничество в области охраны окружающей среды

environmental engineering – техника кондиционирования воздуха

helical fan – пропеллерный (осевой) вентилятор

helical fin – спиральное ребро

helium film – гелиевая пленка

hemispherical thermal emittance – полусфериполусферическое тепловое излучение

mac value (maximum concentration) – предельно допустимая концентрация/(ПДК)

machine – 1. машина/2, механизм

machine room – машинный зал

machinery – compartment машинное отделение

machinist's kit – набор слесарно монтажных инструментов

magnesite brick – магнезитовый кирпич

narrowing – сужение

natural circulation – естественная циркуляция

natural gas liquefaction – сжижение природного газа условиях естественной конвекции

natural-draft burner – горелка с естественной тягой

natural-draft water cooling tower – градирня с естественным движением воздуха

oil cooler – маслоохладитель

operating temperature – рабочая температура

operating temperature range – рабочий диапазон температур

paraffinic oil – парафиновое масло

parallel blade damper – клапан с параллельными лопатками

parallel connection – параллельное соединение

partial central heating – местное центральное отопление

partial derivative – частная производная

partial duty port – перепускное отверстие для снижения производ.

partial load – частичная нагрузка

partial pressure – парциальное давление

partial purification – частичная очистка

partial recovery refrigeration – охлаждение с частичной рекуперацией хладагента

quantity of air – количество воздуха

quantity of fuel – количество топлива

quantity of gas – количество газа

quantity of lubricant – количество смазочного материала

radiator – нагревательный прибор [водяной или паровой отопительной системы]

radiator – радиатор

safety interlock – защитная блокировка

safety of service – эксплуатационная надежность

safety pipe – предохранительная труба

safety pressostat – реле давления

safety switch – предохранительный выключатель

safety thermostat – защитное термореле

toxicity – токсичность

trace – трасса

tracer – 1. регистрирующее устройство 2. трассирующий индикатор

tracer gas – трассирующий газ

tractive force – движущая сила

trail run – пробный ход

trailing edge thickness – толщина кромки ковша

transducer – преобразователь

transductor – магнитный усилитель

unsteady state – неустановившееся состояние

untreated water – сырая вода

up and down airflow control button – кнопка регулирования воздушного потока в вертикальном направлении [вверх и вниз]

upcast shaft – вентиляционная шахта

up-feed distribution – нижняя разводка

vaneaxial fan – осевой вентилятор

vaned opening – выходное отверстие с регулирующими лопатками

vaned outlet – выходное (выпускное) отверстие с жалюзийной решеткой

vane-type pump – крыльчатый насос

vapor – пар

vapor content (ratio) – относительная влажность

vapor control – регулирование п содержания пара

vapor jet cycle – пароструйный цикл

Railway Construction

Concept the railway designates the strip of the earth equipped with rails or surfaces of an artificial construction (a tunnel, the bridge, a platform) which is used for movement of rail vehicles. The railway can consist of one track or several.

The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast (or slab track), plus the underlying subgrade. For clarity it is often referred to as railway track (British English and UIC terminology) or railroad track (predominantly in the United States).

Traditional track structure

Notwithstanding modern technical developments, the overwhelmingly dominant track form worldwide consists of flat-bottom steel rails supported on timber or pre-stressed concrete sleepers (railroad ties in the US), which are themselves laid on crushed stone ballast.

Most railroads with heavy traffic use continuously welded rails supported by sleepers (ties) attached via baseplates which spread the load. A plastic or rubber pad is usually placed between the rail and the tieplate where concrete sleepers (ties) are used. The rail is usually held down to the sleeper (tie) with resilient fastenings, although cut spikes are widely used in North American practice.

Timber sleepers (ties) are of many available timbers, and are often treated with creosote, copper-chrome-arsenic, or other wood preservative. Pre-stressed concrete sleepers (ties) are often used where timber is scarce and where tonnage or speeds are high. Steel is used in some applications.

The track ballast is customarily crushed stone, and the purpose of this is to support the ties and allow some adjustment of their position, while allowing free drainage.

Ballastless track

A disadvantage of traditional track structures is the heavy demand for maintenance, particularly surfacing (tamping) and lining to restore the desired track geometry and smoothness of vehicle running. Weakness of the subgrade and drainage deficiencies also lead to heavy maintenance costs. This can be overcome by using ballastless track. In its simplest form this consists of a continuous slab of concrete (like a highway structure) with the rails supported directly on its upper surface (using a resilient pad).

There are a number of proprietary systems, and variations include continuous in situ placing of a reinforced concrete slab, or alternatively the use of pre-cast pre-stressed concrete units laid on a base layer. Many permutations of design have been put forward.

However ballastless track is very expensive in first cost, and in the case of existing railroads requires closure of the route for a somewhat long period. Its whole life cost can be lower because of the great reduction in maintenance requirement. Ballastless track is usually considered for new very high speed or very high loading routes, in short extensions that require additional strength (i.e. rail station), or for localised replacement where there are exceptional maintenance difficulties.

Ladder track

Ladder track utilizes longitudinal sleepers with gauge restraining cross members, it can be considered a development of Baulk road. Both ballasted and ballastless types exist.

Obsolete track types

For much of the 20th century, rail track used softwood timber ties and jointed rails, and considerable extents of this track type remains on secondary and tertiary routes. The rails were typically of flat bottom section fastened to the ties with dogspikes through a flat tieplate in North America and Australia, and typically of bullhead section carried in cast iron chairs in British and Irish practice.

Jointed rails were used, at first because the technology did not offer any alternative. However the intrinsic weakness in resisting vertical loading results in the ballast support becoming depressed and a heavy maintenance workload is imposed to prevent unacceptable geometrical defects at the joints. The joints also required to be lubricated, and wear at the fishplate (joint bar) mating surfaces needed to be rectified by shimming. For this reason jointed track is not financially appropriate for heavily operated railroads.

Rail

Hot rolled steel in the profile (cross section) of an asymmetrical I-beam is usually used as the surface on which railway wheels run.[1] Unlike some other uses of iron and steel, railway rails are subject to very high stresses and have to be made of very high-quality steel alloy. It took many decades to improve the quality of the materials, including the change from iron to steel. The heavier the rails and the rest of the trackwork, the heavier and faster the trains the track can carry.

Profiles of rail include:

Bullhead rail

Grooved rail

Vignoles rail (flat-bottomed rail)

Flanged T rail

Bridge rail (inverted U)

Barlow rail (inverted V)

North American railroads until the mid- to late-20th century used rails 39 ft (11.89 m) long so they could be carried to and from a worksite in gondola cars (open wagons), often 40 ft (12.2 m) long; as gondola sizes increased, so did rail lengths.

The world's longest rail sections are 120 m (394 ft) long and are made by various companies.

Wooden rails

The earliest rails were made of wood, but these wore out quickly. Hardwood such as Jarrah and Karri were better than softwoods such as Fir. Longitudinal sleepers such as Brunel's baulk road are topped with iron or steel rails that are lighter than they then might otherwise be because of the support of the sleepers.