File Name: building technology and materials .zip
The development of civil engineering in the course of centuries meant a constant struggle with available materials, spans, or heights, active loads, and the forces of nature: water, fire, wind, and earthquakes. While construction activities improve the quality of human life, they also have a significant impact on the environment. The production of construction materials requires energy and generates greenhouse gases.
Construction , also called building construction , the techniques and industry involved in the assembly and erection of structures, primarily those used to provide shelter. Construction is an ancient human activity.
It began with the purely functional need for a controlled environment to moderate the effects of climate. Constructed shelters were one means by which human beings were able to adapt themselves to a wide variety of climates and become a global species. Human shelters were at first very simple and perhaps lasted only a few days or months. Over time, however, even temporary structures evolved into such highly refined forms as the igloo.
Gradually more durable structures began to appear, particularly after the advent of agriculture , when people began to stay in one place for long periods. The first shelters were dwellings, but later other functions, such as food storage and ceremony, were housed in separate buildings.
Some structures began to have symbolic as well as functional value, marking the beginning of the distinction between architecture and building. The history of building is marked by a number of trends. One is the increasing durability of the materials used. Early building materials were perishable, such as leaves, branches, and animal hides.
Later, more durable natural materials—such as clay, stone, and timber—and, finally, synthetic materials—such as brick , concrete , metals, and plastics —were used.
Another is a quest for buildings of ever greater height and span; this was made possible by the development of stronger materials and by knowledge of how materials behave and how to exploit them to greater advantage.
A third major trend involves the degree of control exercised over the interior environment of buildings: increasingly precise regulation of air temperature, light and sound levels, humidity , odours, air speed, and other factors that affect human comfort has been possible. Yet another trend is the change in energy available to the construction process, starting with human muscle power and developing toward the powerful machinery used today.
The present state of construction is complex. There is a wide range of building products and systems which are aimed primarily at groups of building types or markets. The design process for buildings is highly organized and draws upon research establishments that study material properties and performance, code officials who adopt and enforce safety standards, and design professionals who determine user needs and design a building to meet those needs.
The construction process is also highly organized; it includes the manufacturers of building products and systems, the craftsmen who assemble them on the building site, the contractors who employ and coordinate the work of the craftsmen, and consultants who specialize in such aspects as construction management, quality control, and insurance.
Construction today is a significant part of industrial culture , a manifestation of its diversity and complexity and a measure of its mastery of natural forces, which can produce a widely varied built environment to serve the diverse needs of society. This article first traces the history of construction, then surveys its development at the present time. For treatment of the aesthetic considerations of building design, see architecture.
For further treatment of historical development, see art and architecture, Anatolian ; art and architecture, Arabian ; art and architecture, Egyptian ; art and architecture, Iranian ; art and architecture, Mesopotamian ; art and architecture, Syro-Palestinian ; architecture, African ; art and architecture, Oceanic ; architecture, Western ; arts, Central Asian ; arts, East Asian ; arts, Islamic ; arts, Native American ; arts, South Asian ; arts, Southeast Asian.
The hunter-gatherers of the late Stone Age, who moved about a wide area in search of food, built the earliest temporary shelters that appear in the archaeological record. Excavations at a number of sites in Europe dated to before 12, bce show circular rings of stones that are believed to have formed part of such shelters.
They may have braced crude huts made of wooden poles or have weighted down the walls of tents made of animal skins, presumably supported by central poles. A tent illustrates the basic elements of environmental control that are the concern of construction. The tent creates a membrane to shed rain and snow; cold water on the human skin absorbs body heat. The membrane reduces wind speed as well; air over the human skin also promotes heat loss.
It controls heat transfer by keeping out the hot rays of the sun and confining heated air in cold weather. It also blocks out light and provides visual privacy.
The membrane must be supported against the forces of gravity and wind; a structure is necessary. Membranes of hides are strong in tension stresses imposed by stretching forces , but poles must be added to take compression stresses imposed by compacting forces. Indeed, much of the history of construction is the search for more sophisticated solutions to the same basic problems that the tent was set out to solve. The tent has continued in use to the present. The agricultural revolution , dated to about 10, bce , gave a major impetus to construction.
People no longer traveled in search of game or followed their herds but stayed in one place to tend their fields. Dwellings began to be more permanent. Archaeological records are scanty, but in the Middle East are found the remains of whole villages of round dwellings called tholoi , whose walls are made of packed clay ; all traces of roofs have disappeared.
In Europe tholoi were built of dry-laid stone with domed roofs; there are still surviving examples of more recent construction of these beehive structures in the Alps.
In later Middle Eastern tholoi a rectangular antechamber or entrance hall appeared, attached to the main circular chamber—the first examples of the rectangular plan form in building. Still later the circular form was dropped in favour of the rectangle as dwellings were divided into more rooms and more dwellings were placed together in settlements. The tholoi marked an important step in the search for durability; they were the beginning of masonry construction.
Evidence of composite construction of clay and wood , the so-called wattle-and-daub method, is also found in Europe and the Middle East. The walls were made of small saplings or reeds, which were easy to cut with stone tools. They were driven into the ground, tied together laterally with vegetable fibres, and then plastered over with wet clay to give added rigidity and weatherproofing. The roofs have not survived, but the structures were probably covered with crude thatch or bundled reeds.
Both round and rectangular forms are found, usually with central hearths. Heavier timber buildings also appeared in Neolithic New Stone Age cultures , although the difficulties of cutting large trees with stone tools limited the use of sizable timbers to frames.
These frames were usually rectangular in plan, with a central row of columns to support a ridgepole and matching rows of columns along the long walls; rafters were run from the ridgepole to the wall beams. The lateral stability of the frame was achieved by burying the columns deep in the ground; the ridgepole and rafters were then tied to the columns with vegetable fibres.
The usual roofing material was thatch : dried grasses or reeds tied together in small bundles, which in turn were tied in an overlapping pattern to the light wooden poles that spanned between the rafters. Horizontal thatched roofs leak rain badly, but, if they are placed at the proper angle, the rainwater runs off before it has time to soak through.
Primitive builders soon determined the roof pitch that would shed the water but not the thatch. Many types of infill were used in the walls of these frame houses, including clay, wattle and daub , tree bark favoured by American Woodland Indians , and thatch.
In Polynesia and Indonesia , where such houses are still built, they are raised above the ground on stilts for security and dryness; the roofing is often made of leaves and the walls are largely open to allow air movement for natural cooling.
Another variation of the frame was found in Egypt and the Middle East, where timbers were substituted for bundles of reeds. Construction Article Media Additional Info. Article Contents. Print print Print. Table Of Contents. While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. Facebook Twitter.
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These books are used by students of top universities, institutes and colleges. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The journal publishes a wide range of innovative research and application papers which describe laboratory and to a limited extent numerical investigations or report on full scale projects. Multi-part papers are discouraged. Building material is any material which is used for construction purposes. Many naturally occurring substances, such as clay, rocks, sand, and wood, even twigs and leaves, have been used to construct buildings. The manufacturing of building materials is an established industry in many countries and the use of these materials is typically segmented into specific specialty trades, such as carpentry, insulation, plumbing, and roofing work.
Construction , also called building construction , the techniques and industry involved in the assembly and erection of structures, primarily those used to provide shelter. Construction is an ancient human activity. It began with the purely functional need for a controlled environment to moderate the effects of climate. Constructed shelters were one means by which human beings were able to adapt themselves to a wide variety of climates and become a global species. Human shelters were at first very simple and perhaps lasted only a few days or months.
Aerospace Engineering. Engineering Books. Check out the Building Materials and Construction books free download in pdf format. Environmental Engineering 2. Automobile Engineering. Building Materials and Construction books are also useful to most of the students, who are preparing for Competitive Exams.
Materials engineers are responsible for the selection, specification, and quality control of materials to be used in a job. These materials must meet certain classes of criteria or materials properties. These classes of criteria include. In addition to this traditional list of criteria, civil engineers must be concerned with environmental quality. Sustainable development basically recognizes the fact that our designs should be sensitive to the ability of future generations to meet their needs.
Building material is material used for construction. Many naturally occurring substances, such as clay , rocks, sand , and wood , even twigs and leaves, have been used to construct buildings. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic.
Теперь только один человек в АНБ был по должности выше коммандера Стратмора - директор Лиланд Фонтейн, мифический правитель Дворца головоломок, которого никто никогда не видел, лишь изредка слышал, но перед которым все дрожали от страха. Он редко встречался со Стратмором с глазу на глаз, но когда такое случалось, это можно было сравнить с битвой титанов. Фонтейн был гигантом из гигантов, но Стратмора это как будто не касалось. Он отстаивал перед директором свои идеи со спокойствием невозмутимого боксера-профессионала. Даже президент Соединенных Штатов не решался бросать вызов Фонтейну, что не раз позволял себе Стратмор. Для этого нужен был политический иммунитет - или, как в случае Стратмора, политическая индифферентность.
Она хорошо понимала, что в отчаянной ситуации требуются отчаянные меры, в том числе и от АНБ. - Мы не можем его устранить, если ты это имела в виду. Именно это она и хотела узнать.
- Сколько будет сто десять минус тридцать пять и две десятых. - Семьдесят четыре и восемь десятых, - сказала Сьюзан. - Но я не думаю… - С дороги! - закричал Джабба, рванувшись к клавиатуре монитора. - Это и есть ключ к шифру-убийце.
Ее глаза были холодны как лед, а ее обычная мягкость исчезла без следа.
- Он заверил меня, что ТРАНСТЕКСТ в полной исправности. Сказал, что он взламывает коды каждые шесть минут и делал это даже пока мы с ним говорили. Поблагодарил меня за то, что я решил позвонить. - Он лжет, - фыркнула Мидж. - Я два года проверяю отчеты шифровалки.
Не имеет понятия. Рассказ канадца показался ему полным абсурдом, и он подумал, что старик еще не отошел от шока или страдает слабоумием.
Через пять лет, истратив полмиллиона рабочих часов и почти два миллиарда долларов, АН Б вновь доказало жизненность своего девиза. Последний из трех миллионов процессоров размером с почтовую марку занял свое место, все программное обеспечение было установлено, и керамическая оболочка наглухо заделана. ТРАНСТЕКСТ появился на свет. Хотя создававшийся в обстановке повышенной секретности ТРАНСТЕКСТ стал плодом усилий многих умов и принцип его работы не был доступен ни одному человеку в отдельности, он, в сущности, был довольно прост: множество рук делают груз легким. Три миллиона процессоров работали параллельно - считая с неимоверной скоростью, перебирая все мыслимые комбинации символов.
Сьюзан заглянула в распечатку через плечо Джаббы. - Выходит, нас атакует всего лишь первый набросок червя Танкадо. - Набросок или отшлифованный до блеска экземпляр, - проворчал Джабба, - но он дал нам под зад коленом. - Не верю, - возразила Сьюзан. - Танкадо был известен стремлением к совершенству.
Раздался еще один выстрел. Пуля попала в корпус мотоцикла и рикошетом отлетела в сторону. Беккер изо всех сил старался удержаться на шоссе, не дать веспе съехать на обочину.
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