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Construction

Construction

. A crane is readied to lower a barge into the water. This barge will be placed under any cutting work on the bridge to lessen the environmental impact. Note the concrete barricades and snow fencing in place to protect the public and workers.]] In project architecture and civil engineering, construction is the building or assembly of any infrastructure. Although this may be thought of as a single activity, in fact construction is a feat of multitasking. Normally the job is managed by the construction manager, supervised by the project manager, design engineer or project architect. While these people work in offices and make the most money, every construction project requires a large number of laborers to complete the physical task of construction. For the successful execution of a project effective planning is often essential. Those involved with the design and execution of the infrastructure in question must consider the environmental impact of the job, the successful scheduling, budgeting, site safety, inconvenience to the public caused by construction delays, preparing tender documents... The list goes on and on.

Construction

In general, there are three types of construction: (1) building, (2) heavy/highway, and (3) industrial. Each type of construction requires a unique team to plan, design, construct, and maintain the project.

Building construction

preparing tender documents 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, and legal considerations. Many projects of varying sizes reach undesirable end results, such as structural collapse, cost overruns, and/or litigation, as a result of insufficient planning. For this reason, those with experience in the field make detailed plans and maintain careful oversight during the project to ensure a positive outcome. For projects of large size and/or unusual type, the owner will likely establish a team of workers and advisors to create an overall plan. This ensures that the project will proceed in an orderly way to a desirable end. While no set list would establish what is needed or advisable for a particular project, frequently used advisors include mortgage bankers, accountants, lawyers, insurance brokers, architects, and engineers. While their roles overlap, each area of expertise addresses an element of what will be affected by the building construction project.

Heavy/Highway construction

Heavy/Highway construction is the process of adding "infrastructure" to our built environment. Owners of these projects are usually government agencies, either at the national or local level. As in building construction, heavy/highway construction has design, financial, and legal considerations, however these projects are not usually undertaken for-profit, but to service the public interest. In addition, in many countries public agencies must adhere to many legal requirements that require the project to undergo a public bid process. As in building construction, the owner will assemble a team to create an overall plan to ensure that the goals of the project are met.

Industrial construction

Industrial construction, though a relatively small part of the entire construction industry, is a very important component. Owner of these projects are usually large, for-profit, industrial corporations. These corporations are can found in such industries as medicine, petroleum, chemical, power generation, manufacturing, etc. Processes in the industries require highly specialized expertise in planning, design, and construction. As in building and heavy/highway construction, this construction requires a team of individuals to ensure project success.

Design team

In the modern industrialized world, construction usually involves the translation of paper or computer based designs into reality. A formal design team may be assembled to plan the physical proceedings, and to integrate those proceedings with the other parts. The design usually consists of drawings and specifications, usually prepared by a design team including architects, civil engineers, cost engineers (or quantity surveyors), mechanical engineers, electrical engineers, and structural engineers. The design team is most commonly employed by (i.e. in contract with) the property owner. Under this system, once the design is completed by the design team, a number of construction companies or construction management companies may then be asked to make a bid for the work, either based directly on the design, or on the basis of drawings and a bill of quantities provided by a surveyor. Following evaluation of bids, the owner will typically award a contract to the lowest responsible bidder. The modern trend in design is toward integration of previously separated specialties, especially among large firms. In the past, architects, engineers, developers, construction managers, and general contractors were more likely to be entirely separate companies, even in the larger firms. Presently, a firm that is nominally an "architecture" or "construction management" firm is likely to have experts from all related fields as employees, or to have an associated company that provides each necessary skill. Thus, each such firm may offer itself as "one-stop shopping" for a construction project, from beginning to end. This is designated as a "design Build" contract where the contractor is given a performance specification, and must undertake the project from design to construction, while adhering to the performance specifications. Several project structures can assist the owner in this integration, including design-build, partnering, and construction management. In general, each of these project structures allows the owner to integrate the services of architects, engineers, and constructors throughout design and construction. In response, many companies are growing beyond traditional offerings of design or construction services alone, and are placing more emphasis on establishing relationships with other necessary participants through the design-build process. surveyor

Financial advisors

Many construction projects suffer from preventable financial problems. Underbids ask for too little money to complete the project. Cash flow problems exist when the present amount of funding cannot cover the current costs for labor and materials, and because they are a matter of having sufficient funds at a specific time, can arise even when the overall total is enough. Fraud is a problem in many fields, but is notoriously prevalent in the construction field. Financial planning for the project is intended to ensure that a solid plan, with adequate safeguards and contingency plans, is in place before the project is started, and is required to ensure that the plan is properly executed over the life of the project. Mortgage bankers, accountants, and cost engineers are likely participants in creating an overall plan for the financial management of the building construction project. The presence of the mortgage banker is highly likely even in relatively small projects, since the owner's equity in the property is the most obvious source of funding for a building project. Accountants act to study the expected monetary flow over the life of the project, and to monitor the payouts throughout the process. Cost engineers apply expertise to relate the work and materials involved to a proper valuation. Large projects can involve highly complex financial plans. As portions of a project are completed, they may be sold, supplanting one lender or owner for another, while the logistical requirements of having the right trades and materials available for each stage of the building construction project carries forward.

Legal considerations

A construction project must fit into the legal framework governing the property. These include governmental regulations on the use of property, and obligations that are created in the process of construction. The project must adhere to zoning and building code requirements. Constructing a project that fails to adhere to codes will not benefit the owner. Some legal requirements come from malum in se considerations, or the desire to prevent things that are indisputably bad - bridge collapses or explosions. Other legal requirements come from malum prohibitum considerations, or things that are a matter of custom or expectation, such as isolating businesses to a business district and residences to a residential district. An attorney may seek changes or exemptions in the law governing the land where the building will be built, either by arguing that a rule is inapplicable (the bridge design won't collapse), or that the custom is no longer needed (acceptance of live-work spaces has grown in the community). Also, a construction project is a complex net of contracts and other legal obligations, each of which must be carefully considered. A contract is the exchange of a set of obligations between two or more parties, but it is not so simple a matter as trying to get the other side to agree to as much as possible in exchange for as little as possible. The time element in construction means that a delay costs money, and in cases of bottlenecks, the delay can be extremely expensive. Thus, the contracts must be designed to ensure that each side is capable of performing the obligations set out. Contracts that set out clear expectations and clear paths to accomplishing those expectations are far more likely to result in the project flowing smoothly, whereas poorly drafted contracts lead to confusion and collapse. Legal advisors in the beginning of a construction project seek to identify ambiguities and other potential sources of trouble in the contract structure, and to present options for preventing problems. Throughout the process of the project, they work to avoid and resolve conflicts that arise. In each case, the lawyer facilitates an exchange of obligations that matches the reality of the project.

Interaction of expertise

Design, finance, and legal aspects overlap and interrelate. The design must be not only structurally sound and appropriate for the use and location, but must also be financially possible to build, and legal to use. The financial structure must accommodate the need for building the design provided, and must pay amounts that are legally owed. The legal structure must integrate the design into the surrounding legal framework, and enforces the financial consequences of the construction process.

Construction trades

- Brickwork
- Carpentry
- Cladding
- Drainage
- Framing
- Glazing
- Heating, Ventilation, and Air-conditioning
- Insulation
- Joinery
- Masonry
- Painting and Decorating
- Plastering
- Plumbing
- Roofing
- Electrician
- Ironworker
- Heavy Equipment Operator (see: Engineering vehicles)
- Stonemason

Temporary works

- Shoring
- Rigging

Construction materials

- Concrete
- Wood including Lumber and Timber
- Steel
- Stone
- Glass
- Drywall
- Straw-bales
- Adobe (sun-dried mud)
- Brick (kiln oven-baked clay)
- Rammed earth
- Ferrocement
- aggregate (composite)
- Asphalt
- Structural insulated panel (composite)

Structural elements

- Foundations
- Floating-raft system
- Roof
- Wall

External links

- [http://constructionmagazine.info Construction Magazine]
- [http://www.urbanheaven.co.nr Urban Heaven] - Building Construction/Discussion Forum NR
- [http://www.architectureweek.com/2000/0524/culture_1-1.html What is the Culture of Building?] by Howard Davis.
- [http://www.servicemagic.com/construction/ The State of Construction Jobs Online] by Daniel Howard
- [http://www.indiaconstruction.in Professions in Construction Industry]
- Cost overruns [http://www.realestatejournal.com/regionalnews/midwest/20011102-grid.html Chicago's Millennium Park] [http://www.askthebuilder.com/416_Cost_Overruns.shtml Small Home Projects] [http://www.taxpayer.net/TCS/wastebasket/transportation/4-12-00.htm Boston's Big Dig]
- Legal considerations [http://egov.cityofchicago.org:80/city/webportal/portalDeptCategoryAction.do?BV_SessionID=@@@@0555318591.1100643684@@@@&BV_EngineID=cccdaddddiheflfcefecelldffhdfhg.0&deptCategoryOID=-536883465&contentType=COC_EDITORIAL&topChannelName=Dept&entityName=Buildings&deptMainCategoryOID=-536883465 Chicago Building Code]

Barge

A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Most barges are not self-propelled and need to be moved by tugboats towing or pushing them. Barges on canals (towed by draft animals on an adjacent towpath) contended with the railway in the early industrial revolution but were outcompeted in the carriage of high value items due to the higher speed, falling costs, and route flexibility of rail transport. Barges are still used today for low value bulk items, as the cost of hauling goods by barge is very low. Self propelled barges may be used as such when traveling downstream or upstream in placid waters and operated as an unpowered barge with the assistance of a tugboat when traveling upstream in faster waters. Types of barges:
- Barracks barge (living quarters)
- Dry bulk cargo barge (coal, rock, grain, etc.)
- Liquid cargo barge (fresh water, finished petroleum products)
- Railcar barge (with tracks and using special loading/offloading facilities such as a barge slip)
- Vehicular barge, often used to transport vehicles to natural shorelines such as beaches
- Royal barge (ceremonial)
- Lighter On the UK canal system, the term barge is used to describe a boat wider than a narrowboat. The people who move barges are often known as lightermen. In the U.S. deckhands perform the labor and are supervised by a leadman and or the mate. The Captain and Pilot steer the towboat. The towboat pushes one or more barges that are held together with rigging and is called collectively the tow. The crew live aboard the towboat as it travels along the inland river system and or the intracoastal waterways. These towboats travel between ports and are also called line haul boats. A barge pole is used by lightermen to fend off the barge as it nears other vessels or a wharf. These long poles have given rise to the saying, "I wouldn't touch that (subject/thing) with a barge pole." The meaning is that something is so unseemly or contentious that the person wants to avoid it or being associated with it at all costs. A common variation is to say, "I wouldn't touch that with a (insert length) barge pole." Typically the length for small avoidance is "ten foot": The greater the length, the more the sayer feels it is to be avoided. The barge pole mentioned above is properly called a "pike pole."

Etymology

barge is attested from 1300, from Old French barge, from Vulgar Latin barga. The word originally could refer to any small boat, the modern meaning arose around 1480. bark "small ship" is attested from 1420, from Old French barque, from Vulgar Latin barca (400 AD). The more precise meaning "three-masted ship" arose in the 17th century, and often takes the French spelling for disambiguation. Both are probably derived from a Latin
- barica, from Greek baris "Egyptian boat", ultimately from m Coptic bari "small boat."

External links

- [http://www.barges.org DBA - Dutch Barge Association] Living aboard ex-commercial barges or any other type of broad-beam inland waterways craft Category:Boat types

Water

:This article focuses on water as it is experienced in everyday life. See water (molecule) for information on the chemical and physical properties of pure water (H₂O, hydrogen oxide). Water (from the Old English word wæter; c.f German "Wasser", from PIE
- wod-or, "water") is a tasteless, odorless, and nearly colorless (it has a slight hint of blue) substance in its pure form that is essential to all known forms of life and is known also as the most universal solvent. Water is an abundant substance on Earth. It exists in many places and forms. It appears mostly in the oceans and polar ice caps, but also as clouds, rain water, rivers, freshwater aquifers, and sea ice. On the planet, water is continuously moving through the cycle involving evaporation, precipitation, and runoff to the sea. Water fit for human consumption is called potable water. This natural resource is becoming more scarce in certain places as human population in those places increases, and its availability is a major social and economic concern.

Molecular properties

Forms of water

potable water] Water takes many different shapes on earth: water vapor and clouds in the sky, waves and icebergs in the sea, glaciers in the mountain, aquifers in the ground, to name but a few. Through evaporation, precipitation, and runoff, water is continuously flowing from one form to another, in what is called the water cycle. Because of the importance of precipitation to agriculture, and to mankind in general, different names are given to its various forms: while rain is common in most countries, other phenomena are quite surprising when seen for the first time. Hail, snow, fog or dew are examples. When appropriately lit, water drops in the air can refract sunlight to produce rainbows. Similarly, water runoffs have played major roles in human history as rivers and irrigation brought the water needed for agriculture. Rivers and seas offered opportunity for travel and commerce. Through erosion, runoffs played a major part in shaping the environment providing river valleys and deltas which provide rich soil and level ground for the establishment of population centers. Water also infiltrates the ground and goes into aquifers. This groundwater later flows back to the surface in springs, or more spectacularly in hot springs and geysers. Groundwater is also extracted artificially in wells. Because water can contain many different substances, it can taste or smell very differently. In fact, humans and other animals have developed their senses to be able to evaluate the drinkability of water: animals generally dislike the taste of salty sea water and the putrid swamps and favor the purer water of a mountain spring or aquifer.

Water in biology

From a biological standpoint, water has many distinct properties that are critical for the proliferation of life that set it apart from other substances. Water carries out this role by allowing organic compounds to react in ways that ultimately allows replication. It is a good solvent and has a high surface tension, and thus allows organic compounds and living things to be transported in it. Fresh water has its greatest density at 4°C, then becoming less dense as it freezes or heats up from this point. As a stable, polar molecule prevalent in the atmosphere, it plays an important atmospheric role as an absorber of infrared radiation, crucial in the atmospheric greenhouse effect without of which, the average surface temperature would be −18° Celsius. Water also has an unusually high specific heat, which plays many roles in regulating global and regional climate, such as the Gulf Stream climate, allowing life to survive. Water is a very good solvent, chemically not unlike ammonia, and dissolves many types of substances, such as various salts and sugar, and facilitates their chemical interaction, which aids complex metabolisms. Some substances, however, do not mix well with water, including oils and other hydrophobic substances. Cell membranes, composed of lipids and proteins, take advantage of this property to carefully control interactions between their contents and external chemicals. This is facilitated somewhat by the surface tension of water. Water drops are stable due to the high surface tension of water caused by the strong intermolecular forces called cohesive forces. This can be seen when small quantities of water are put onto a nonsoluble surface such as polythene: the water stays together as drops. On extremely clean glass the water may form a thin film because the molecular forces between glass and water molecules (adhesive forces) are stronger than the cohesive forces. This property plays a key role in plant transpiration. A simple but environmentally important and unique property of water is that its common solid form, ice, floats on the liquid. This solid phase is less dense than liquid water, due to the geometry of the strong hydrogen bonds which are formed only at lower temperatures. For almost all other substances and for all other 11 uncommon phases of water ice except ice-XI, the solid form is more dense than the liquid form. Fresh water is most dense at 4°C, and will sink by convection as it cools to that temperature, and if it becomes colder it will rise instead. This reversal will cause deep water to remain warmer than shallower freezing water, so that ice in a body of water will form first at the surface and progress downward, while the majority of the water underneath will hold a constant 4°C. This effectively insulates a lake floor from the cold. While this behavior may seem obvious, even intuitive, it should be noted that almost all other chemicals are denser as solids than they are as liquids, and freeze from the bottom up. Life on earth has evolved with and adapted itself to the important features of water. The existence of abundant liquid, vapor and solid forms of water on Earth has been an important factor in the abundant colonization of Earth's various environments by life-forms adapted to those varying and often extreme conditions. Civilizations have historically flourished around rivers and major waterways; Mesopotamia, the so-called cradle of civilization, is situated between two major rivers. Large metropolises like London, Paris, New York, and Tokyo owe their success in part to their easy accessibility via water and the resultant expansion of trade. Islands with safe water ports, like Singapore and Hong Kong, have flourished for precisely this reason. In places such as North Africa and the Middle East, where water is scarcer, access to clean drinking water was and is a major factor in human development.

Astronomical position of Earth and impact on its water

Mesopotamia The coexistence of the solid, liquid, and gaseous phases of water on Earth is vital to the origin, evolution, and continued existence of life on Earth. However, if the Earth's location in the solar system were even marginally closer or further from the Sun (ie, a million miles or so), the conditions which allow the three forms to be present simultaneously would be far less likely to exist. Earth's mass allows gravity to hold an atmosphere. Water vapor and carbon dioxide in the atmosphere provides a greenhouse effect which helps maintain a relatively steady surface temperature. If Earth were less massive, a thinner atmosphere would cause temperature extremes preventing the accumulation of water except in polar ice caps (as on Mars). According to the solar nebula model of the solar system's formation, Earth's mass may be largely due to its distance from the Sun. The distance between Earth and the Sun and the combination of solar radiation received and the greenhouse effect of the atmosphere ensures that its surface is neither too cold nor too hot for liquid water. If Earth were more distant, most water would be frozen. If Earth were nearer to the Sun, its higher surface temperature would limit the formation of ice caps, or cause water to exist only as vapor. In the former case, the low albedo of oceans would cause Earth to absorb more solar energy. In the second case, a runaway greenhouse effect and inhospitable conditions similar to Venus would result. It has been proposed that life itself may maintain the conditions that have allowed its continued existence. The surface temperature of Earth has been relatively constant through geologic time despite varying solar flux, indicating that a dynamic process governs Earth's temperature via a combination of greenhouse gases and surface or atmospheric albedo. This proposal is known as the Gaia hypothesis.

Human uses of water

Gaia hypothesis All known forms of life depend on water. Water is a vital part of many metabolic processes within the body. Significant quantities of water are used during the digestion of food. (Note however that some bacteria and plant seeds can enter a cryptobiotic state for an indefinite period when dehydrated, and come back to life when returned to a wet environment) About 72% of the fat free mass of the human body is made of water. To function properly the body requires between one and seven litres of water per day to avoid dehydration, the precise amount depending on the level of activity, temperature, humidity, and other factors. It is not clear how much water intake is needed by healthy people. However, for those who do not have kidney problems, it is rather difficult to drink too much water, but (especially in warm humid weather and while exercising) dangerous to drink too little. People do often drink far more water than necessary while exercising, however, putting them at risk of water intoxication, which is frequently fatal. The "fact" that a person should consume eight glasses of water per day cannot be traced back to a scientific source. However, leading dieticians and nutritionists will tell you that this is the RDI (Recommended Daily Intake) of water. [http://ajpregu.physiology.org/cgi/content/full/283/5/R993]. The latest dietary reference intake report by the National Research Council recommended 2.7 liters of water total (including food sources) for women and 3.7 liters for men[http://www.iom.edu/report.asp?id=18495]. Water is lost from the body in urine and feces, through sweating, and by exhalation of water vapor in the breath. Humans require water that does not contain too much salt or other impurities. Common impurities include chemicals and/or harmful bacteria, such as crypto sporidium. Some solutes are acceptable and even desirable for perceived taste enhancement and to provide needed electrolytes.

Water as a precious resource

:See water resources for information about fresh water supplies. fresh water Because of the growth of world population and other factors, the availability of drinking water per capita is shrinking. The issue of water shortage can be solved through more production, better distribution and less waste of it. For this reason, water is a strategic resource for many countries. Many battles and wars, such as the Six-Day War in the Middle East, have been fought to gain access to it. Experts predict more trouble ahead because of the world's growing population, increasing contamination through pollution, and global warming. UNESCO's World Water Development Report (WWDR, 2003) from its World Water Assessment Program indicates that, in the next 20 years, the quantity of water available to everyone is predicted to decrease by 30%. 40% of the world's inhabitants currently have insufficient fresh water for minimal hygiene. More than 2.2 million people died in 2000 from diseases related to the consumption of contaminated water or drought. In 2004, the UK charity WaterAid reported that a child dies every 15 seconds due to easily preventable water-related diseases. Some have predicted that clean water will become the "next oil", making Canada, with this resource in abundance, possibly the richest country in the world.

Regulating water distribution

Drinking water is often collected at springs or extracted from artificial borings in the ground, or wells. Building more wells in adequate places is thus a possible way to produce more water assuming the aquifers can supply an adequate flow. Other water sources are the rainwater and river or lake water. This surface water, however, must be purified for human consumption. This may involve removal of undissolved substances, dissolved substances and harmful microbes. Popular methods are filtering with sand which only removes undissolved material while chlorination and boiling kill harmful microbes. Distillation does all three functions. More advanced techniques exist, such as reverse osmosis. Desalination of abundant ocean or seawater is a more expensive solution used in coastal arid climates. The distribution of drinking water is done through municipal water systems or as bottled water. Governments in many countries have programs to distribute water to the needy at no charge. Others argue that the market mechanism and free enterprise are best to manage this rare resource, and to finance the boring of wells or the construction of dams and reservoirs. Reducing waste, that is using drinking water only for human consumption, is another option. In some cities, such as Hong Kong, sea water is extensively used for flushing toilets citywide in order to conserve fresh water resources. Polluting water may be the biggest single misuse of water; to the extent that a pollutant limits other uses of the water, it becomes a waste of the resource, regardless of benefits to the pollutor. Pharmaceuticals consumed by humans often end up in the waterways and can have detrimental effects on aquatic life if they bioaccumulate and if they are not biodegradable.

The impact of water on human culture

Water is considered a purifier in most religions, including Christianity, Islam, Judaism, and Shinto. For instance, baptism in Christian churches is done with water. In addition, a ritual bath in pure water is performed for the dead in many religions including Judaism and Islam. In Islam, the daily Salah can only be done after ablution (Wodoo), that is, washing parts of the body in clean water. In Shinto, water is used in almost all rituals to cleanse a person or an area. Water is often believed to have spiritual powers. In Celtic mythology, Sulis is the local goddess of thermal springs; in Hinduism, the Ganga is also personified as a goddess. Alternatively, gods can be patrons of particular springs, river or lakes: for example in Greek and Roman mythology, Peneus was a river god, one of the three thousand Oceanids. The Greek philosopher Empedocles held that water is one of the four classical elements along with fire, earth and air, and was regarded as the ylem, or basic stuff of the universe. Water was considered cold and moist. In the theory of the four bodily humours, water was associated with phlegm. Water was also one of the Five Elements in traditional Chinese philosophy, along with earth, fire, wood, and metal. A common misconception about water is that it is a powerful conductor of electricity. Any electrical properties observable in water are due to the ions of mineral salts and carbon dioxide dissolved in it. Water does self-ionize (two water molecules become one hydroxide anion and one hydronium cation), but only at a very slight, almost immeasurable level. Pure water can also be electrolized into oxygen and hydrogen gases but without any dissolved ions, this is a very slow process and thus very little current is conducted. Many bottled water companies exploit another common misconception, advertising both purity and taste, even though pure water is tasteless.

External links

- [http://www.lsbu.ac.uk/water/phase.html Phase diagrams of water]
- [http://www.publicforuminstitute.org/issues/oceans/index.htm Oceans and Water Issues Page]
- [http://www.greenfacts.org/water-disinfectants/index.htm Scientific Facts on Water disinfectants] A faithful summary by GreenFacts of a leading scientific consensus report on Drinking Water Disinfectants published by the International Programme on Chemical Safety of the WHO.
- [http://www.hkc22.com/residentialwater.html Residential water problems and markets] Study paper from Helmut Kaiser Consultancy
- [http://www.hkc22.com/watermarketsworldwide.html Water markets worldwide] Study paper from Helmut Kaiser Consultancy
- [http://www.worldwaterforum.org/ World Water Forum]
- [http://www.unesco.org/water/wwap/ World Water Assessment Program]
- [http://unesdoc.unesco.org/images/0012/001295/129556e.pdf United Nations' World Water Development Report]
- [http://www.gemswater.org/ United Nations GEMS/Water Programme]
- [http://www.lsbu.ac.uk/water/ Water Structure and Behaviour]
- [http://www.wateraid.org/ WaterAid]
- [http://www.sahra.arizona.edu/newswatch/ SAHRA—Global Water Newswatch]
- [http://www.siwi.org/ Stockholm International Water Institute] (SIWI)
- [http://www.c-win.org/ California Water Impact Network (C-WIN)]
- [http://news.bbc.co.uk/2/hi/science/nature/3752590.stm BBC: The water debate]
- [http://www.geocities.com/tapvsbottled/ Tap Water Vs Bottled Water] - Interesting site providing facts about tap and bottled water.
- [http://www.emagazine.com/september-october_2003/0903feat1.html E the Environmental Magazine piece on bottled water] (Oct 2003).
- [http://www.iapws.org/ International Association for the Properties of Water and Steam]
- [http://ga.water.usgs.gov/edu/watercycle.html US Geological Survey: Comprehensive discussion of the water cycle, in many languages]
- [http://www.dartmouth.edu/~etrnsfer/water.htm Why is water blue?]
- [http://www.water.org.uk/home/resources-and-links/water-for-health/ask-about/adults Water requirements in adults]
- [http://www.hkc22.com/environmentaltechnology.html/ Climate change raises markets for environmental technology, drinking water and clean energies]

References

- OA Jones, JN Lester and N Voulvoulis, Pharmaceuticals: a threat to drinking water? TRENDS in Biotechnology 23(4): 163, 2005
- Category:Beverages Category:Hydrology Category:Materials Category:Natural resources Category:Nutrition zh-min-nan:Chúi als:Wasser ko:물 ja:水 ms:Air simple:Water th:น้ำ

Bridge

:This article is about the edifice (it is mostly an index to articles concerning specific bridge types). For other meanings, see bridge (disambiguation). bridge (disambiguation) A bridge is a structure built to span a gorge, valley, road, railroad track, river, body of water, or any other physical obstacle. Designs may be built higher than otherwise needed in order to allow other traffic (particularly ship traffic) beneath. The purpose of a bridge is to allow easier passage by providing a continuous more uniform more easily navigable route via what would otherwise be an uneven or impossible path for the particular kind of thing travelling or being transported, whether people, vehicles, trains, ships, liquids or whatever else.

History

The first bridges were spans made of wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. The arch was first used by the Roman Empire for bridges and aqueducts, some of which still stand today. The Romans also had cement, which reduced the variation of strength found in natural stone. Brick and mortar bridges were built after the Roman era, as the technology for cement was lost then later rediscovered. Rope bridges, a simple type of suspension bridge, were used by the Inca civilization in the Andes mountains of South America, just prior to European colonization in the 1500s. During the 18th century there were many innovations in the design of timber bridges by Hans Ulrich, Johannes Grubenmann, and others. The first engineering book on building bridges was written by Hubert Gautier in 1716. With the rise of the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron did not have the tensile strength to support large loads. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel.

Etymology

The Oxford English Dictionary traces the origin of the word bridge to an Old Norse word bryggja, meaning "landing stage, gangway, or movable pier".

Types of bridges

Bridges may be classified by their use or by their structure.

By use

A bridge is usually designed for trains, pedestrian or road traffic, a pipeline or waterway for water transport or barge traffic. In some cases there may be restrictions in use. For example, it may be a bridge carrying a highway and forbidden for pedestrians and bicycles, or a pedestrian bridge, possibly also for bicycles. An aqueduct is a bridge that carries water, resembling a viaduct.

Decorative and ceremonial bridges

To create a beautiful image, some bridges are built much taller than necessary. This type, often found in east-asian style gardens, is called a Moon bridge, evoking a rising full moon. Other garden bridges may cross only a dry bed of stream washed pebbles, intended only to convey an impression of a stream. Often in palaces a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. A set of five bridges cross a sinuous waterway in an important courtyard of the Forbidden City in Beijing, China. The central bridge was reserved exclusively for the use of the Emperor, Empress, and their attendants.

Index to types of bridges and bridge related topics

Image:NagasakiMeganebashi.jpg|Arch bridge Image:Pont_du_gard.jpg|Aqueduct Image:Baileycoppename.jpg|Bailey bridge Image:UniversityBridge-1Clip.jpg|Bascule bridge Image:Small footbridge.jpg|Beam bridge Image:Concrete box girder bridge.JPG|Box girder bridge Image:ThreeTwrBrCenter.jpg|Cable-stayed bridge Image:CaissonSchematic.jpg|Caisson Image:ForthBridgeEdinburgh.jpg|Cantilever bridge Image:Puente del Alamillo.jpg|Cantilever spar cable-stayed bridge Image:Tarr steps clapper bridge.jpg|Clapper bridge Image:Australia sydney-404.jpg|Compression arch suspended-deck bridge Image:Guilford vermont covered bridge 20040820.jpg|Covered bridge Image:CurlingBridgeClip.jpg|Curling bridge Image:Fort ticonderoga drawbridge to demilune.jpg|Drawbridge Image:Hoernbruecke.jpg|Folding bridge Image:IRBSideViewClip.jpg|Inca rope bridge Image:JetwayAtVancouverBC.jpg|Jetway Image:Guilford vermont bridge covered bridge interior 20040820.jpg|Lattice bridge Image:BNSFBridgeClip.jpg|Lift bridge Image:Vallorcine footpath bridge 2003-12-13.jpg|Log bridge Image:SFTGMoonBridge.jpg|Moon bridge Image:PlateGirderUnderTracks.jpg|Plate girder bridge Image:ArmyPontoonBr.jpg|Pontoon bridge Image:Uppsala Ultunabron02 2005-06-16.jpg|Retractable bridge
(Thrust bridge) Image:ProposedSFOBBEasternSpan.jpg|Self-anchored suspension bridge Image:SegmentalBridgeFtLauderdale.jpg|Segmental bridge Image:WinnepegBridge.jpg|Side-spar cable-stayed bridge Image:CapilanoBridge.jpg|Simple suspension bridge Image:StepStoneBridge.jpg|Step-stone bridge Image:BridgeSubmerging4.jpg|Submersible bridge Image:suspension.bridge.bristol.arp.750pix.jpg|Suspension bridge Image:Railway swing bridge.jpg|Swing bridge Image:Millenium_bridge_close.jpg|Tilt bridge Image:Paying Toll on passing a Bridge From a Painted Window in the Cathedral of Tournay Fifteenth Century.png|Toll bridge Image:Newport.transporter.750pix.jpg|Transporter bridge Image:AlhambraTrestle.jpg|Trestle Image:Eastbound_over_SCB.jpg|Truss arch bridge Image:RRTrussBridgeSideView.jpg|Truss bridge Image:Conwy Castle 2.jpg|Tubular bridge Image:Toronto-bloorviaduct.jpg|Viaduct Image:NoImageYetRectFramed.png|Weigh bridge Image:BoxerwoodDotComZigZag.jpg|Zig-zag bridge

Bridge structural and evolutionary taxonomy

Zig-zag bridge Bridges may be classified by how the four forces of tension, compression, bending and shear are distributed through their structure. Most bridges will employ all of the principle forces to some degree, but only a few will predominate. The separation of forces may be quite clear, as in a suspension or cable-stayed span; the elements in tension are distinct in shape and placement. In other cases the forces may be distributed among a large number of members, as in a truss, or not clearly discernible to a casual observer as in a box beam. Bridges can also be classified by their lineage, which is shown as the vertical axis on the diagram to the right.

Efficiency

A bridge's structural efficiency may be considered to be the ratio of load carried to bridge weight, given a specific set of material types. In one common challenge young students are to be divided into groups of two or three and then to be given a fixed quantity of wood sticks, a specific distance to span, and a given glue, and then to construct a bridge that will be tested to destruction by the progressive addition of load at the center of the span. The bridge taking the greatest load is by this test the most structurally efficient. A bridge's economic efficiency will be site and traffic dependent, the ratio of savings by having a bridge (instead of, for example, a ferry, or a longer road route) compared to its cost. For a given site, kind of bridge employed and the materials used determine the total cost, a lifetime cost composed of materials, labor, machinery, engineering, cost of money, maintenance, refurbishment, risk potential, and ultimately, demolition and associated disposal, recycling, and reuse. Bridges employing only compression are relatively inefficient structurally, but may be highly cost efficient where suitable materials are available near the site. For medium spans, trusses or box beams are usually most economical, while in some cases, the appearance of the bridge may be more important than its cost efficiency. The longest spans usually require suspension bridges.

Notable bridges

- Akashi-Kaikyo Bridge - Japan, with the longest section span of 1.9 km.
- Forth Railway Bridge - Scotland, one of the most famous cantilever bridges in the world.
- Golden Gate Bridge - USA, arguably the most beautiful of its type.
- The Iron Bridge - England, the world's first iron bridge.
- Confederation Bridge - Canada, world's longest bridge over waters that freeze.
- Jamuna Bridge- Bangladesh, longest rail-road bridge in south asia , 2nd longest in world.
- Lake Pontchartrain Causeway - USA, spanning Lake Pontchartrain in south Louisiana, it is the longest bridge in the world at 23.87 miles (38.41 km).
- Lupu Bridge- China, longest single steel arch.
- Mackinac Bridge - USA, Opened to traffic in 1957, connecting the two peninsulas of Michigan; held the title of the world's longest two tower suspension bridge between anchorages until the 1990s.
- Mahatma Gandhi Setu - India, the longest river bridge in the world.
- Menai Suspension Bridge - Wales, first road suspension bridge in the world.
- Millau Viaduct - France, tallest bridge in the world.
- Overtoun Bridge, - Scotland, dogs have leaped to their deaths from this bridge, leading to urban legends.
- Penang Bridge - Malaysia, longest bridge in Southeast Asia.
- Québec Bridge - Canada, largest cantilever bridge in the world.
- San Francisco-Oakland Bay Bridge - USA, especially for seismic retrofit and eastern span replacement.
- Sundial Bridge - USA, a dramatic single cantilever spar cable stayed span for pedestrians.
- Sydney Harbour Bridge - Australia, arguably the best-known suspended-deck compression arch bridge.
- Tacoma Narrows Bridge - USA, famous for its collapse due to aerodynamic effects.
- Tatara Bridge - Japan, largest span cable-stayed bridge.
- Tower Bridge - London, England, and a symbol of this city.
- Tyne Bridge - England, one of Northern England's most iconic structures.
- Trajan's bridge - Romania, ancient Roman bridge over the river Danube, only fragments visible.
- Vasco da Gama Bridge - Portugal, the longest bridge in Europe at 17.2 km.
- Victoria Falls Bridge - linking Zimbabwe to Zambia, built in 1905 as part of the projected Cape-Cairo railway.
- Zakim Bunker Hill Bridge - USA, built during Boston's Big Dig, the widest cable-stayed bridge.

External links

- [http://www.structurae.de/en/ Structurae] - International Database and Gallery of Structures.
- [http://www.asce.org/history/hp_bridges.html American Society of Civil Engineers] History and Heritage of Civil Engineering - Bridges
- [http://www.historicbridges.org/index.htm Historic Bridges of Michigan and Elsewhere] Photos, information, and maps of historic bridges in and around Michigan. Also has a links page with links to bridge databases in other regions of the U.S.A.
- [http://www.brantacan.co.uk/bridges.htm Bridge Building — Art and Science] Comprehensive explanations about bridges.
- [http://www.garrettsbridges.com/index.html Model Bridge Building]
- [http://pghbridges.com/basics.htm Bridge Basics] A guide to bridge terminology and styles
- [http://www.chinapage.com/bridge/shanghai/lupu/lupu.html Shanghai lupu] Chinese bridge site showing suspended deck arch construction and completion.
- [http://www.bridgebuilder-game.com BridgeBuilder] - Great game where you design a bridge and see if a train will drive over it safely.
- [http://finance.groups.yahoo.com/group/RRbridge/ RRbridge]- Discussion group focused on railroad bridges, trestles, and viaducts. Hosted by Yahoo! Groups
- [http://filebox.vt.edu/users/aschaeff/titlepage.html Bridge disasters]
- [http://www.nireland.com/bridgeman/Dictionary.htm A dictionary of bridge terms]
- [http://bridges.lib.lehigh.edu/BookListpage.html/ Digital Bridge Library at Lehigh University]
- [http://bobjagendorf.smugmug.com/gallery/119358 Bridge Photos]
- [http://flickr.com/photos/tags/bridge Flickr: Photos tagged with bridge] Category:Buildings and structures
- Category:Coastal construction ko:다리 ms:Jambatan ja:橋 simple:Bridge th:สะพาน

Barricade

A barricade is any object or structure that creates a barrier or obstacle to control, block passage or force the flow of traffic in the desired direction. As a military term, the barricade denotes any improvised field fortification, most notably on the city streets during urban warfare. It is also used to describe the devices actually used for this purpose. Some examples are: urban warfare
- A temporary traffic barricade, pictured here, which has the goal of dissuading passage into a protected or hazardous area.
- A large slab of cement or specially formed plastic tub of water, whose goal is to actively prevent forcible passage by a vehicle. Polish barricades during the Warsaw Uprising Image:Warsaw Uprising baricade2.jpg|Polish barricade with a captured Hetzer tank destroyer built in Image:Warsaw Uprising baricade.jpg|Polish barricade with a street car Image:Barykada.jpg|Other captured Hetzer at other baricade

Snow

) high forests.]] Snow is precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes. Since it is composed of small rough particles it is a granular material. It has an open and therefore soft structure, unless packed by external pressure. Snow is commonly formed when water vapor undergoes deposition high in the atmosphere at a temperature of less than 0°C (32°F), and then falls to the ground.

Types

Flurries are similar to rainshowers and only last for short periods of time. Snow which has partially thawed while falling is called sleet; if this re-freezes on further descent, the resulting small icy pellets or granules of snow are called soft hail. A related phenomenon is freezing rain, where rain falls on ground sufficiently cold for it to freeze on contact, forming black ice on the ground. A snow squall is a brief, very intense snowstorm while a blizzard is a long-lasting snow storm with intense snowfall and usually high winds. Particularly severe storms can create whiteout conditions where visibility is reduced to less than 1 m, while blizzards can also create large snowdrifts. A ground blizzard occurs when a strong wind drives already fallen snow to create drifts and whiteouts. Snow can be also manufactured using snow cannons, which actually create tiny granules more like soft hail (this is sometimes called "grits" by those in the southern U.S. for its likeness to the texture of the food). In recent years, snow cannons have been produced that create more natural looking snow, but these machines are very expensive and are found only on the most prestigious places.

Occurrence

Snowfall varies by time and location, including geographic latitude, elevation and other factors which affect weather in general. In latitudes closer to the equator, there is less chance of snow fall, 35° N and 40°S are often quoted as a rough delimiter. The western coasts of the major continents remain snowless to much higher latitudes. As temperature decreases with altitude, high mountains, even at or near the Equator, have permanent snow cover on their top. Examples include Mount Kilimanjaro in Tanzania and the Tropical Andes in South America; the only snow actually on the Equator is at 4,690 m altitude on the south slope of Volcán Cayambe in Ecuador (Google Earth images). Conversely, many regions of the Arctic and Antarctic receive very little precipitation and therefore little snow despite the bitter cold (below a certain temperature, air essentially loses its ability to carry water vapor). Although density of fresh snow varies widely, a guide is that the depth of snowfall is 10 times that of a rainfall containing the same mass of water. Substantial snowfall sometimes disrupts infrastructure and services even in regions that are accustomed to them. Traffic may be snarled or even completely stop. Basic infrastructure such as electricity, phones and gas supply can be shut down. This can lead to a snow day, a day on which school or other services are cancelled owing to unusually heavy snowfall. In areas that normally have very little snow, this may occur even with light accumulation — something often made fun of by those people used to colder climates, where streets would remain passable given the same amount of snow. The highest seasonally cumulative precipitation of snow ever measured in the world was on Mount Baker, Washington, U.S.A during 1998–1999 season when they received 28.96 meters (1,140 in); this surpassed the previous record holder, Mount Rainier, Washington, U.S.A which during 1971–1972 season received 28.5 meters (1,122 in) of snow; and the world record daily precipitation was recorded in Silver Lake, Colorado, U.S.A in 1921 1.93 meters (76 in). See also: List of Countries receiving snowfall

Recreation

List of Countries receiving snowfall Forms of recreation dependent on snow:
- Many winter sports, such as skiing, snowmobiling, snowshoeing and snowboarding
- Playing with a sled or riding in a sleigh
- Building a snowman or snow fort
- Throwing snowballs mutually in a snowball fight or at others to tease them. (Humans seem to be the only animal that throw their snowballs. Pygmy chimpanzees have been known to carry snowballs around, but never to throw them.) Where snow is scarce but the temperature is low enough, snow cannons may be used to produce an adequate amount for such sports. Tightly packed snow may be used as a construction material in, for example, Inuit snow houses. The world´s biggest snowcastle is built in Kemi, Finland, every winter.

Geometry

Finland An interesting question is why the arms of snowflakes are symmetrical, and why no two snowflakes appear to be identical. The answer is believed to be due to the fact that the distances between snowflakes are much greater than the distances across snowflakes. The symmetry of snowflake arms is always six-fold, which arises from the hexagonal crystal structure of ordinary ice (known as ice I_h) along its 'basal' plane. There are, broadly, two possible explanations for the symmetry of snowflakes. Firstly, there could be communication (information transfer) between the arms, such that growth in each arm affects the growth in each other arm. Surface tension or phonons are among the ways that such communication could occur. The other explanation, which appears to be the prevalent view, is that the arms of a snowflake grow independently in an environment that is believed to be rapidly varying in temperature, humidity and so on. This environment is believed to be relatively spatially homogenous on the scale of a single flake, leading to the arms growing to a high level of visual similarity by responding in identical ways to identical conditions, much in the same way that unrelated trees respond to environmental changes by growing near-identical sets of tree rings. The difference in the environment in scales larger than a snowflake leads to the observed lack of correlation between the shapes of different snowflakes. tree ring However, the concept that no two snowflakes are alike is incorrect; it is entirely possible, but unlikely, that a pair of snowflakes may be visually identical if their environments were similar enough, either because they grew very near one another, or simply by chance. The American Meteorological Society has reported that matching snow crystals were discovered by Nancy Knight of the National Center for Atmospheric Research. The crystals were not flakes in the usual sense but rather hollow hexagonal prisms. ;High-resolution gallery Image:Snow crystals.png Image:Snow crystals 2.png Image:Snow crystals 2b.png Image:LT-SEM snow crystals.jpg Image:LT-SEM snow crystal magnification series-3.jpg

Media

External links

- [http://www.nsdl.arm.gov/Library/glossary.shtml#snowflake National Science Digital Library - Snowflake]
- [http://www.its.caltech.edu/~atomic/snowcrystals/faqs/faqs.htm Kenneth G. Libbrecht's Snowflake FAQ]
- http://www.its.caltech.edu/~atomic/snowcrystals/photos/photos.htm Category:Snow ko:눈 (날씨) ja:雪 simple:Snow th:หิมะ

Architecture

Architecture (in Greek αρχή = start and τέχνη = craftsmanship) is the art and science of designing buildings and structures. A wider definition would include within its scope the design of the total built environment, from the macrolevel of town planning, urban design, and landscape architecture to the microlevel of furniture. furniture, Athens, Greece]] However, the widest definition in modern use refers to the organization, articulation, and interfaces of any built (or To Be Built— TBB) entity, whether a building or a communications' network. That is, an architecture, in its broadest sense, shows how the components of a built or TBB entity fit together. An architecture may be considered a translation between a user's needs and a builder's building instructions, or requirements. The components of an architecture may be already built items, or specified items (items whose building requirements have been completed), or To Be Specified items (items whose building requirements have not yet been been completed, and for which only user or builder needs may be assigned).

Introduction

The skills of the architect are used in complex building types such as the skyscraper, hospital, stadium, airport, etc. to less complicated projects such as commercial and residential buildings and development. Many pieces of architecture can be seen as cultural and political symbols. The role of the architect, though changing, has been central to the successful (and sometimes unsuccessful) design and implementation of the built environment in which we live.

Scope and intentions

According to the very earliest surviving work on the subject, Vitruvius' De architectura, good buildings satisfy three core principles: Firmness, Commodity, and Delight; architecture can be said to be a balance and coordination among these three elements, with none overpowering the others. A modern day definition sees architecture as addressing aesthetic, structural and functional considerations. However, looked at another way, function itself is seen as encompassing all criteria, including aesthetic and psychological ones. Architecture is a multi-disciplinary field, including within its fold mathematics, science, art, technology, social sciences, politics, history, philosophy, and so on. In Vitruvius' words: "Architecture is a science, arising out of many other sciences, and adorned with much and varied learning: by the help of which a judgement is formed of those works which are the result of other arts". He adds that an architect should be well versed in fields such as music, astronomy, etc. Philosophy is a particular favourite; in fact the approach of an architect to their subject is often called their philosophy. Rationalism, empiricism, structuralism, poststructuralism, and phenomenology are some topics from philosophy that have influenced architecture. phenomenology, Italy]] # Translation of firmitatis utilitatis venustatis [http://penelope.uchicago.edu/Thayer/L/Roman/Texts/Vitruvius/home.html] due to Henry Wotton, 1624 [http://www.gardenvisit.com/landscape/LIH/history/vitruvius.htm#ch1-3].

Theory and practice

Architecture and buildings

The difference between architecture and building is a subject matter that has engaged the attention of many. According to Nikolaus Pevsner, European historian of the early 20th century, "A bicycle shed is a building, Lincoln Cathedral is a piece of architecture". In current thinking, the division is not too clear. Bernard Rudofsky's famous Architecture Without Architects consolidated a whole range of structures designed by ordinary people into the realm of architecture. Architecture is also the art of designing the human built environment. Buildings, landscaping, and street designs may be used to impart both functional as well as aesthetic character to a project. Siding and roofing materials and colors may be used to enhance or blend buildings with the environment. Building features such as cornices, gables, entrances, window treatments and borders may be used to soften or enhance portions of a building. Landscaping may be used to create privacy and block direct views from or to a site and enhance buildings with colorful plants and trees. Street side features such as decorative lighting, benches, meandering walkways, and bicycle lanes may enhance a site for passersby, pedestrians, and cyclists.

Architectural history

Architecture first evolved out of the dynamics between needs (shelter, security, worship, etc.) and means (available building materials and attendant skills). Prehistoric and primitive architecture constitute this early stage. As humans progressed and knowledge began to be formalised through oral traditions and practices, architecture evolved into a craft. Here there is first a process of trial and error, and later improvisation or replication of a successful trial. What is termed Vernacular architecture continues to be produced in many parts of the world. Vernacular architecture, India]] Early human settlements were essentially rural. As surplus of production began to occur, rural societies transformed into urban ones and cities began to evolve. In many ancient civilisations such as the Egyptians' and Mesopotamians' architecture and urbanism reflected the constant engagement with the divine and the supernatural. However, the architecture and urbanism of the Classical civilisations such as the Greek and the Roman evolved from more civic ideas and new building types emerged. Architectural styles developed and texts on architecture began to be written. These became canons to be followed in important works, especially religious architecture. Some examples of canons are the works of Vitruvius, the Kaogongji of ancient China and Vaastu Shastra in ancient India. In Europe in the Classical and Medieval periods, buildings were not attributed to specific individual architects who remained anonymous. Guilds were formed by craftsmen to organise their trade. Over time the complexity of buildings and their types increased. General civil construction such as roads and bridges began to be built. Many new building types such as schools, hospitals, and recreational facilities emerged. Islamic architecture has a long and complex history beginning in the 7th century CE. Examples can be found throughout the countries that are, or were, Islamic - from Morocco and Spain to Iran, and Indonesia. Other examples can be found in areas where Muslims are a minority. Islamic architecture includes mosques, madrasas, caravansarais, palaces, and mausolea of this large region. With the Renaissance and its emphasis on the individual and humanity rather than religion, and with all its attendant progress and achievements, a new chapter began. Buildings were ascribed to specific architects - Michaelangelo, Brunelleschi, Leonardo da Vinci - and the cult of the individual had begun. But there was no dividing line between artist, architect and engineer, or any of the related vocations. At this stage, it was still possible for an artist to design a bridge as the level of structural calculations involved were within the scope of the generalist. With the consolidation of knowledge in scientific fields such as engineering and the rise of new materials and technology, the architect began to lose ground on the technical aspects of building. He therefore cornered for himself another playing field - that of aesthetics. There was the rise of the "gentleman architect" who usually dealt with wealthy clients and concentrated predominantly on visual qualities derived usually from historical prototypes. In the 19th century Ecole des Beaux Arts in France, the training was toward producing quick sketch schemes involving beautiful drawings without much emphasis on context. France, USA]] Meanwhile, the Industrial Revolution laid open the door for mass consumption and aesthetics started becoming a criterion even for the middle class as ornamented products, once within the province of expensive craftmanship, became cheaper under machine production. Industrial Revolution, India]] The dissatisfaction with such a general situation at the turn of the twentieth century gave rise to many new lines of thought that in architecture served as precursors to Modern Architecture. Notable among these is the Deutscher Werkbund, formed in 1907 to produce better quality machine made objects. The rise of the profession of industrial design is usually placed here. Following this lead, the Bauhaus school, founded in Germany in 1919, consciously rejected history and looked at architecture as a synthesis of art, craft, and technology. When Modern architecture first began to be practiced, it was an avant-garde movement with moral, philosophical, and aesthetic underpinnings. Truth was sought by rejecting history and turning to function as the generator of form. Architects became prominent figures and were termed masters. Later modern architecture moved into the realm of mass production due to its simplicity and economy. However, a reduction in quality of modern architecture was perceived by the general public from the 1960s. Some reasons cited for this are its lack of meaning, sterility, ugliness, uniformity, and psychological effects. The architectural profession responded to this partly by attempting a more populist architecture at the visual level, even if at the expense of sacrificing depth for shallowness, a direction called Postmodernism. Robert Venturi's contention that a "decorated shed" (an ordinary building which is functionally designed inside and embellished on the outside) was better than a "duck" (a building in which the whole form and its function are considered together) gives an idea of this approach. Another part of the profession, and also some non-architects, responded by going to what they considered the root of the problem. They felt that architecture was not a personal philosophical or aesthetic pursuit by individualists; rather it had to consider everyday needs of people and use technology to give a livable environment. The Design Methodology Movement involving people such as Chris Jones, Christopher Alexander started searching for more people-orientated designs. Extensive studies on areas such as behavioural, environmental, and social sciences were done and started informing the design process. As many other concerns began to be recognised and complexity of buildings began to increase in terms of aspects such as services, architecture started becoming more multi-disciplinary than ever. Architecture now required a team of professionals in its making, an architect being one among the many, sometimes the leader, sometimes not. This is the state of the profession today. However, individuality is still cherished and sought for in the design of buildings seen as cultural symbols - the museum or fine arts centre has become a showcase for new experiments in style: today Deconstructivism, tomorrow maybe something else.

External links

- [http://www.pygmies.info/camps.html African Pygmies Architecture]
- [http://www.aia.org/ American Institute of Architects]
- [http://www.architectsindex.com/ ArchitectsIndex - Directory of UK Architects along with work examples]
- [http://www.architypes.net/ Architypes - Wiki of architecture design principles and patterns]
- [http://www.architecture.com/ Architecture.com - Courtesy of the Royal Institute of British Architects]
- [http://www.archpedia.com/ Archpedia - architecture encyclopedia]
- [http://www.vernarch.com/ Center for vernacular Architecture-Bangalore-India]
- [http://st-takla.org/Gallery/Gallery-Coptic-Orthodox-Architecture-01.html Christian Coptic Orthodox Architecture] at http://St-Takla.org
- [http://www.cupola.com/bldgstr1.htm Cupola - Building and Structure Photo Galleries]
- [http://www.danda.be/ Danda - News and reviews on architecture]
- [http://www.iab.org.br/ Instituto de Arquitetos do Brasil]
- [http://www.islamicarchitecture.org Islamic Architecture]
- [http://www.archinform.net/ Archinform - International Architecture Database]
- [http://architect.architecture.sk Famous architects]
- [http://www.galinsky.com/ Galinsky - People enjoying buildings worldwide]
- [http://www.glasssteelandstone.com/ Global Architecture Encyclopedia - Glass Steel and Stone]
- [http://www.thehopkinscompany.com/glossary/glossary.html Glossary of Architectural Terms]
- [http://www.greatbuildings.com/ Great Buildings Collection]
- [http://www.nyc-architecture.com/ New York architecture images]
- [http://www.riba.org Royal Institute of British Architects]
- [http://www.sah.org/ Society of Architectural Historians]
- [http://www.vitruvio.ch/ Vitruvio]
- [http://worldheritage-forum.net/de/ Worldheritage-Forum: Weblog and Information on UNESCO World Heritage topics] Category:Applied sciences Category:Arts ko:건축 ms:Seni bina ja:建築学 simple:Architecture th:สถาปัตยกรรมศาสตร์

Civil engineering

.]] In modern usage, civil engineering is a broad field of engineering that deals with the planning, construction, and maintenance of fixed structures, or public works, as they are related to earth, water, or civilization and their processes. Most civil engineering today deals with roads, structures, water supply, sewer, flood control and traffic. In essence civil engineering is the profession which makes the world a more habitable place to live. Engineering has developed from observations of the ways natural and constructed systems react and from the development of empirical equations that provide bases for design. Civil engineering is the broadest of the engineering fields. In fact engineering was once divided into only two fields--military and civil. All the engineering specialties have derived from civil engineering. Civil engineering is still an umbrella field comprised of many related specialities.

Sub-disciplines of civil engineering

General civil engineering

General civil engineering is concerned with the overall interface of fixed projects with the greater world. General civil engineers work closely with surveyors and specialized civil engineers to fit and serve fixed projects within their given site, community and terrain by designing grading, drainage (flood control), paving, water supply, sewer service, electric and communications supply and land (real property) divisions. General engineers spend much of their time visiting project sites, developing community/neighborhood consensus, and preparing construction plans.

Structural engineering

Main article: Structural engineering Structural engineering is concerned with the design of bridges, buildings, offshore oil platforms, dams etc. Structural design and structural analysis are components of structural engineering and a key component in the structural design process. This involves computing the stresses and forces at work within a structure. There are some structural engineers who work in non-typical areas, designing aircraft, spacecraft and even biomedical devices. Major design concerns are building seismic resistant structures and seismically retrofitting existing structures.

Geotechnical engineering

Main article: Geotechnical engineering The main subject of the studies also known as soil mechanics is concerned with soil properties, mechanics of soil particles, compression and swelling of soils, seepage, slopes, retaining walls, foundations, footings, ground and rock anchors, use of synthetic tensile materials in soil structures, soil-structure interaction and soil dynamics. Geotechnical engineering covers this field of studies for application in engineering. The importance of geotechnical engineering can hardly be overstated: buildings must be supported by reliable foundations. Dam design and construction reducing flooding of lower drainage areas is an important subject of geotechnical engineering.

Transportation engineering

Main article: Transportation engineering Transportation engineering is primarily concerned with motorized road transportation, especially in North America. This includes areas such as queueing theory and traffic flow planning, roadway geometric design and driver behavior patterns. Simulation of traffic operation is performed through use of trip generation, traffic assignment algorithms which can be highly complex computational problems. Other, more specialized areas of transportation engineering are concerned with the designs of non-road transportation facilities, such as rail systems, airports, and ports.

Environmental engineering

Main article: Environmental engineering Environmental engineering deals with the treatment of chemical, biological, and/or thermal waste, the purification of water and air, and the remediation of contaminated sites, due to prior waste disposal or accidental contamination. Among the topics covered by environmental engineering are water purification, sewage treatment, and hazardous waste management. Environmental engineering is related to the fields of hydrology, geohydrology and meteorology insofar as knowledge of (ground)water and flows are required to understand pollutant transport. Environmental engineers are also involved in pollution reduction, "green engineering," and industrial ecology. Environmental engineering also deals with the gathering of information on the environmental consequences of proposed actions and the assessment of effects of proposed actions for the purpose of assisting society and policy makers in the decision making process. Environmental engineering is the contemporary term for sanitary engineering. Some other terms in use are public health engineering and environmental health engineering.

Hydraulic engineering

Main article: Hydraulic engineering Hydraulic engineering is concerned with the flow and conveyance of fluids, principally water. This area of engineering is intimately related to the design of pipelines, water distribution systems, drainage facilities (including bridges, dams, channels, culverts, levees, and storm sewers), canals, and to both sanitary and environmental engineering. Hydraulic engineers design these facilities using the concepts of