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Pontoon Bridge
A pontoon bridge (or ponton bridge), also known as a floating bridge, is a bridge that uses float (nautical), floats or shallow-draft (hull), draft boats to support a continuous deck for pedestrian and vehicle travel. The buoyancy of the supports limits the maximum load that they can carry. Most pontoon bridges are temporary and used in wartime and civil emergencies. There are permanent pontoon bridges in civilian use that can carry highway traffic; generally, the relatively high potential for collapse and sinking (e.g. due to waves and collisions) and high continuous maintenance costs makes pontoons unattractive for most civilian construction. Permanent floating bridges are useful for sheltered water crossings if it is not considered economically feasible to suspend a bridge from anchored Pier (architecture), piers (such as in deep water). Such bridges can require a section that is elevated or can be raised or removed to allow waterborne traffic to pass. Notable permanent pontoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Army
The United States Army (USA) is the primary Land warfare, land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United States Constitution (1789).See alsTitle 10, Subtitle B, Chapter 301, Section 3001 It operates under the authority, direction, and control of the United States Secretary of Defense, United States secretary of defense. It is one of the six armed forces and one of the eight uniformed services of the United States. The Army is the most senior branch in order of precedence amongst the armed services. It has its roots in the Continental Army, formed on 14 June 1775 to fight against the British for independence during the American Revolutionary War (1775–1783). After the Revolutionary War, the Congress of the Confederation created the United States Army on 3 June 1784 to replace the disbanded Continental Army.Library of CongressJournals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operation Dawn 8
The First Battle of al-Faw was a battle of the Iran–Iraq War, fought on the al-Faw peninsula between 10 February and 10 March 1986. The Iranian operation is considered to be one of Iran's greatest achievements in the Iran–Iraq War. The Iranians were able to capture the al-Faw peninsula, cutting off Iraqi access to the Persian Gulf in the process; this in turn hardened Iraqi attitudes to prosecute the war. The Faw peninsula was later recaptured by Iraqi forces near the end of the war. On 9 February 1986, Iran launched Operation Dawn 8, a sophisticated and carefully planned amphibious assault across the Shatt al-Arab (Arvand Rud) river against the Iraqi troops defending the strategic al-Faw peninsula, which connects Iraq to the Persian Gulf. The Iranians defeated the Iraqi defenders, mostly Iraqi Popular Army, capturing the tip of the peninsula, including Iraq's main air control and warning center covering Persian Gulf, as well as limiting Iraq's access to the ocean. Ira ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guard Rail
Guard rails, guardrails, railings or protective guarding, in general, are a boundary feature and may be a means to prevent or deter access to dangerous or off-limits areas while allowing light and visibility in a greater way than a fence. Common shapes are flat, rounded edge, and tubular in horizontal railings, whereas tetraform spear-headed or ball-finialled are most common in vertical railings around homes. Park and garden railings commonly in metalworking feature swirls, leaves, plate metal areas and/or Motif (visual arts), motifs particularly on and beside gates. High security railings (particularly if in flat metal then a type of palisade) may instead feature jagged points and most metals are well-suited to anti-climb paint. A handrail is less restrictive on its own than a guard rail and provides support. Public safety Many public spaces are fitted with guard rails as a means of protection against accidental falls. Any abrupt change in elevation where the higher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stringer (aircraft)
In engineering, a longeron or stringer is a load-bearing component of a framework. The term is commonly used in connection with aircraft fuselages and automobile chassis. Longerons are used in conjunction with stringers to form structural frameworks. Aircraft In an aircraft fuselage, stringers are attached to formers (also called frames) and run in the longitudinal direction of the aircraft. They are primarily responsible for transferring the aerodynamic loads acting on the skin onto the frames and formers. In the wings or horizontal stabilizer, longerons run spanwise (from wing root to wing tip) and attach between the ribs. The primary function here also is to transfer the bending loads acting on the wings onto the ribs and spar. The terms "longeron" and "stringer" are sometimes used interchangeably. Historically, though, there is a subtle difference between the two terms. If the longitudinal members in a fuselage are few in number (usually 4 to 8) and run all along the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Load
A structural load or structural action is a mechanical load (more generally a force) applied to Structural engineering#Structural elements, structural elements. A load causes stress (physics), stress, deformation (engineering), deformation, displacement (vector), displacement or acceleration in a structure. Structural analysis, a discipline in engineering, analyzes the effects of loads on structures and structural elements. Excess load may cause structural failure, so this should be considered and controlled during the design of a structure. Particular mechanical structures—such as aircraft, satellites, rockets, space stations, ships, and submarines—are subject to their own particular structural loads and actions. Engineers often evaluate structural loads based upon published regulations, contracts, or specifications. Accepted technical standards are used for acceptance testing and inspection. Types In civil engineering, specified loads are the best estimate of the actual l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Displacement (fluid)
In fluid mechanics, displacement occurs when an object is largely immersed in a fluid, pushing it out of the way and taking its place. The volume of the fluid displaced can then be measured, and from this, the volume of the immersed object can be deduced: the volume of the immersed object will be exactly equal to the volume of the displaced fluid. An object immersed in a liquid displaces an amount of fluid equal to the object's volume. Thus, buoyancy is expressed through Archimedes' principle, which states that the weight of the object is reduced by its volume multiplied by the density Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' (or ''d'') can also be u ... of the fluid. If the weight of the object is less than this displaced quantity, the object floats; if more, it sinks. The amount of fluid displace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archimedes' Principle
Archimedes' principle states that the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially, is equal to the weight of the fluid that the body displaces. Archimedes' principle is a law of physics fundamental to fluid mechanics. It was formulated by Archimedes of Syracuse. Explanation In '' On Floating Bodies'', Archimedes suggested that (c. 246 BC): Archimedes' principle allows the buoyancy of any floating object partially or fully immersed in a fluid to be calculated. The downward force on the object is simply its weight. The upward, or buoyant, force on the object is that stated by Archimedes' principle above. Thus, the net force on the object is the difference between the magnitudes of the buoyant force and its weight. If this net force is positive, the object rises; if negative, the object sinks; and if zero, the object is neutrally buoyant—that is, it remains in place without either rising or sinking. In simple words, Archim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civil Engineer
A civil engineer is a person who practices civil engineering – the application of planning, designing, constructing, maintaining, and operating infrastructure while protecting the public and environmental health, as well as improving existing infrastructure that may have been neglected. Civil engineering is one of the oldest engineering disciplines because it deals with constructed environment including planning, designing, and overseeing construction and maintenance of building structures, and facilities, such as roads, railroads, airports, bridges, harbors, channels, dams, irrigation projects, pipelines, power plants, and water and sewage systems. The term "civil engineer" was established by John Smeaton in 1750 to contrast engineers working on civil projects with the military engineers, who worked on armaments and defenses. Over time, various sub-disciplines of civil engineering have become recognized and much of military engineering has been absorbed by civil engineering. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Longest Pontoon Bridge In The World, Spanning Russellville And Dardanelle, Arkansas
''The'' is a grammatical article in English, denoting nouns that are already or about to be mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The'' is the most frequently used word in the English language; studies and analyses of texts have found it to account for seven percent of all printed English-language words. It is derived from gendered articles in Old English which combined in Middle English and now has a single form used with nouns of any gender. The word can be used with both singular and plural nouns, and with a noun that starts with any letter. This is different from many other languages, which have different forms of the definite article for different genders or numbers. Pronunciation In most dialects, "the" is pronounced as (with the voiced dental fricative followed by a schwa) when followed by a consonant sound, and as (homophone of the archaic pronoun ''thee' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combat Engineers
A combat engineer (also called pioneer or sapper) is a type of soldier who performs military engineering tasks in support of land forces combat operations. Combat engineers perform a variety of military engineering, Tunnel warfare, tunnel and land mine, mine warfare tasks, as well as construction and demolition duties in and out of combat zones. Combat engineers facilitate the mobility of friendly forces while impeding that of the enemy. They also work to assure the survivability of friendly forces, building fighting positions, fortifications, and roads. They conduct demolition missions and clear minefields manually or through use of Military engineering vehicle, specialized vehicles. Common combat engineer missions include construction and breaching of trenches, tank traps and other obstacles and fortifications; obstacle emplacement and bunker construction; route clearance and reconnaissance; bridge and road construction or destruction; emplacement and clearance of land mines; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Theater Of Operation
The European Theater of Operations, United States Army (ETOUSA) was a theater of Operations responsible for directing United States Army operations throughout the European theatre of World War II, from 1942 to 1945. It commanded Army Ground Forces (AGF), United States Army Air Forces (USAAF), and Army Service Forces (ASF) operations north of Italy and the Mediterranean coast. It was bordered to the south by the North African Theater of Operations, United States Army (NATOUSA), which later became the Mediterranean Theater of Operations, United States Army (MTOUSA). The term ''theater of operations'' was defined in the US Army field manuals as ''the land and sea areas to be invaded or defended, including areas necessary for administrative activities incident to the military operations''. In accordance with the experience of World War I, it was usually conceived of as a large land mass over which continuous operations would take place and was divided into two chief areas-the combat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
