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Strand Jack
A strand jack (also known as strandjack) is a jack used to lift very heavy (e.g. thousands of tons or more with multiple jacks) loads for construction and engineering purposes. Strandjacking was invented by VSL Australia's Patrick Kilkeary & Bruce Ramsay in 1969 for concrete post tensioning systems, and is now widely used for heavy lifting, to erect bridges, offshore structures, refineries, power stations, major buildings and other structures where the use of conventional cranes is either impractical or too expensive. Use Strand jacks can be used horizontally for pulling objects and structures, and are widely used in the oil and gas industry for skidded loadouts. Oil rigs of 38,000 t have been moved in this way from the place of construction on to a barge. Since multiple jacks can be operated simultaneously by hydraulic controllers, they can be used in tandem to lift very large loads of thousands of tons. Tandem use of even two cranes is a very difficult operation. How it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freybrücke Berlin-Spandau-Juni 2016-27-DSCF0177
The Freybrücke (lit. English: Frey Bridge) is an arch bridge located in the Wilhelmstadt district of the Berlin borough of Spandau. It carries Heerstraße (federal road 2/5) over the Havel and Havelseenweg, connecting Pichelsdorf with the Pichelswerder peninsula. The structure spanning 157.90 meters, serves about 60,000 motorists daily. The original road bridge, measuring 174 meters in length, was built in 1908-1909 based on plans by civil engineer Karl Bernhard. Despite being designated as a listed structure, this older bridge was demolished due to significant damage, driven by economic considerations as of 2014. The new bridge, retaining the same name, was inaugurated in December 2016. Initially referred to as the Havelbrücke (Havel bridge), the bridge was renamed Freybrücke in 1913 by a decision of the Osthavelland district. This renaming was intended to pay tribute to the "meritorious leader" of the construction of the Döberitzer Heerstraße (today known as Heerstraße) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jack (device)
A jack is a mechanical lifting device used to apply great forces or lift heavy loads. A mechanical jack employs a screw thread for lifting heavy equipment. A hydraulic jack uses hydraulic power. The most common form is a car jack, floor jack or garage jack, which lifts vehicles so that maintenance can be performed. Jacks are usually rated for a maximum lifting capacity (for example, 1.5 tons or 3 tons). Industrial jacks can be rated for many tons of load. Etymology The personal name ''Jack'', which came into English usage around the thirteenth century as a nickname form of ''John'', came in the sixteenth century to be used as a colloquial word for 'a man (of low status)' (much as in the modern usage 'jack of all trades, master of none'). From here, the word was 'applied to things which in some way take the place of a lad or man, or save human labour'. The first attestation in the ''Oxford English Dictionary'' of ''jack'' in the sense 'a machine, usually portable, for lifting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vorspann System Losinger
VSL International (for Vorspann System Losinger) is a specialist construction company founded in 1954. VSL contributes to engineering, building, repairing, upgrading and preserving transport infrastructure (bridges, tunnels, retained earth walls for roads), buildings and energy production facilities. Based in Switzerland, VSL is owned by French construction company Bouygues. VSL specialises in post-tensioned concrete, stay-cable systems and heavy lifting, while its subsidiary Intrafor focuses on ground engineering and foundations. The company has also developed its proprietary systems, mostly related to post-tensioning and stay-cable, and has 370 patents. History In 1943, the Swiss construction company Losinger started to build post-tensioned bridges and began the development of its own post-tensioning system. The patent of this wire-based system was registered in 1954 and Vorspann System Losinger was created to help develop this activity. The patent was first applied in 195 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prestressed Concrete
Prestressed concrete is a form of concrete used in construction. It is substantially "prestressed" ( compressed) during production, in a manner that strengthens it against tensile forces which will exist when in service. Post-tensioned concreted is "structural concrete in which internal stresses have been introduced to reduce potential tensile stresses in the concrete resulting from loads." This compression is produced by the tensioning of high-strength "tendons" located within or adjacent to the concrete and is done to improve the performance of the concrete in service. Tendons may consist of single wires, multi-wire strands or threaded bars that are most commonly made from high-tensile steels, carbon fiber or aramid fiber. The essence of prestressed concrete is that once the initial compression has been applied, the resulting material has the characteristics of high-strength concrete when subject to any subsequent compression forces and of ductile high-strength steel when sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tonne
The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United States customary units), and the long ton ( British imperial units). It is equivalent to approximately 2204.6 pounds, 1.102 short tons, and 0.984 long tons. The official SI unit is the megagram (symbol: Mg), a less common way to express the same mass. Symbol and abbreviations The BIPM symbol for the tonne is t, adopted at the same time as the unit in 1879.Table 6 . BIPM. Retrieved on 2011-07-10. Its use is also official for the metric ton in the United States, having been adopted by the United States |
Barge
Barge nowadays generally refers to a flat-bottomed inland waterway vessel which does not have its own means of mechanical propulsion. The first modern barges were pulled by tugs, but nowadays most are pushed by pusher boats, or other vessels. The term barge has a rich history, and therefore there are many other types of barges. History of the barge 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 of Barque as "three-masted sailing vessel" arose in the 17th century, and often takes the French spelling for disambiguation. Both are probably derived from the Latin ''barica'', from Greek ''baris'' "Egyptian boat", from Coptic ''bari'' "small boat", hieroglyphic Egyptian D58-G29-M17-M17-D21-P1 and similar ''b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic
Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concerns gases. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on the applied engineering using the properties of fluids. In its fluid power applications, hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids. Hydraulic topics range through some parts of science and most of engineering modules, and cover concepts such as pipe flow, dam design, fluidics and fluid control circuitry. The principles of hydraulics are in use naturally in the human body within the vascular system and erectile tissue. Free surface hydraulics is the branch of hydraulics dealing with free surface flow, such as occurring in rivers, canals, lakes, estuar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Symphyta) are commonly called caterpillars as well. Both lepidopteran and symphytan larvae have eruciform body shapes. Caterpillars of most species eat plant material ( often leaves), but not all; some (about 1%) eat insects, and some are even cannibalistic. Some feed on other animal products. For example, clothes moths feed on wool, and horn moths feed on the hooves and horns of dead ungulates. Caterpillars are typically voracious feeders and many of them are among the most serious of agricultural pests. In fact, many moth species are best known in their caterpillar stages because of the damage they cause to fruits and other agricultural produce, whereas the moths are obscure and do no direct harm. Conversely, various species of caterpi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fingertip Feel
A finger is a limb of the body and a type of digit, an organ of manipulation and sensation found in the hands of most of the Tetrapods, so also with humans and other primates. Most land vertebrates have five fingers ( Pentadactyly). Chambers 1998 p. 603 Oxford Illustrated pp. 311, 380 Land vertebrate fingers The five-rayed anterior limbs of terrestrial vertebrates can be derived phylogenetically from the pectoral fins of fish. Within the taxa of the terrestrial vertebrates, the basic pentadactyl plan, and thus also the fingers and phalanges, undergo many variations. Morphologically the different fingers of terrestrial vertebrates are homolog. The wings of birds and those of bats are not homologous, they are analogue flight organs. However, the phalanges within them are homologous. Chimpanzees have lower limbs that are specialized for manipulation, and (arguably) have fingers on their lower limbs as well. In the case of Primates in general, the digits of the hand a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kursk Submarine Disaster
The nuclear-powered Project 949A ''Antey'' (''Oscar II'' class) submarine '' APL Kursk'' (Russian: ) sank in an accident on 12 August 2000 in the Barents Sea, during the first major Russian naval exercise in more than 10 years, and all 118 personnel on board were killed. The crews of nearby ships felt the initial explosion and a second, much larger explosion, but the Russian Navy did not realise that an accident had occurred and did not initiate a search for the sub for over six hours. The submarine's emergency rescue buoy had been intentionally disabled during an earlier mission and it took more than 16 hours to locate the sunken boat. Over four days, the Russian Navy repeatedly failed in its attempts to attach four different diving bells and submersibles to the escape hatch of the submarine. Its response was criticised as slow and inept. Officials misled and manipulated the public and news media, and refused help from other countries' ships nearby. President Vladimir Putin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Costa Concordia Disaster
On 13 January 2012, the eight-year-old Costa Cruises vessel ''Costa Concordia'' was on the last leg of a cruise around the Mediterranean Sea when she deviated from her planned route at Isola del Giglio, Tuscany, sailed closer to the island, and struck a rock formation on the sea floor. This caused the ship to list and then capsize, landing unevenly on an underwater ledge. Although a six-hour rescue effort brought most of the passengers ashore, 33 people died:27 passengers, five crew, and later, a member of the salvage team. An investigation focused on shortcomings in the procedures followed by ''Costa Concordia'' crew and the actions of her captain, Francesco Schettino, who left the ship prematurely. He left about 300 passengers on board the sinking vessel, most of whom were rescued by helicopter or motorboats in the area. Schettino was found guilty of manslaughter and sentenced to 16 years in prison. Despite receiving its own share of criticism, Costa Cruises and its parent c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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