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Ground Freezing
Ground freezing is a construction technique used in circumstances where soil needs to be stabilized so it will not collapse next to excavations, or to prevent contaminants spilled into soil from being leached away. Ground freezing has been used for at least one hundred years. Pipes are run through the soil to be frozen, and then refrigerants are run through the pipes, freezing the soil. Frozen soil can be as hard as concrete. Design Some ground freezing projects use common salt brine as the refrigerant, but other projects benefit from using more exotic refrigerants, like liquid nitrogen. or solid carbon dioxide ('dry ice'). Examples Soil contaminated with radioactive elements that leaked from Japan's Fukushima Daiichi nuclear power plant was contained through ground freezing. A project in Boston Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Fina ...
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Ground Freezing System In Operation While Commuter Trains Run Through The Big Dig
Ground may refer to: Geology * Land, the solid terrestrial surface of the Earth * Soil, a mixture of clay, sand and organic matter present on the surface of the Earth Electricity * Ground (electricity), the reference point in an electrical circuit from which voltages are measured * Earthing system, part of an electrical installation that connects with the Earth's conductive surface * Ground and neutral, closely related terms Law * Ground (often grounds), in law, a rational motive or basis for a belief, conviction, or action taken, such as a legal action or argument: * Grounds for divorce, regulations specifying the circumstances under which a person will be granted a divorce Music * ''Ground'' (album), the second album by the Nels Cline Trio * "Ground" (song), one of the songs in the debut album of the Filipino rock band Rivermaya * Ground bass, in music, a bass part that continually repeats, while the melody and harmony over it change * '' The Ground'', a 2005 album by No ...
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Cross Section Of A Ground Freezing Pipe As Used In The Big Dig
A cross is a religious symbol consisting of two intersecting lines, usually perpendicular to each other. The lines usually run vertically and horizontally. A cross of oblique lines, in the shape of the Latin letter X, is termed a saltire in heraldic terminology. The cross shape has been widely officially recognized as an absolute and exclusive religious symbol of Christianity from an early period in that religion's history.''Christianity: an introduction''
by Alister E. McGrath 2006 pages 321-323
Before then, it was used as a religious or cultural symbol throughout , in

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Salt Brine
Brine (or briny water) is a high-concentration solution of salt (typically sodium chloride or calcium chloride) in water. In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking (pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization (fresh water recovery). In nature Brines are produced in multiple ways in nature. Modification of seawater via evaporation results in the concentration of salts in the res ...
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Liquid Nitrogen
Liquid nitrogen (LN2) is nitrogen in a liquid state at cryogenics, low temperature. Liquid nitrogen has a boiling point of about . It is produced industrially by fractional distillation of liquid air. It is a colorless, mobile liquid whose viscosity is about one-tenth that of acetone (i.e. roughly one-thirtieth that of water at room temperature). Liquid nitrogen is widely used as a coolant. Physical properties The diatomic character of the N2 molecule is retained after liquefaction. The weak van der Waals interaction between the N2 molecules results in little interatomic attraction. This is the cause of nitrogen's unusually low boiling point. The temperature of liquid nitrogen can readily be reduced to its freezing point by placing it in a vacuum chamber pumped by a vacuum pump. Liquid nitrogen's efficiency as a coolant is limited by the fact that it boils immediately on contact with a warmer object, enveloping the object in an insulating layer of nitrogen gas bubbles. Thi ...
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Dry Ice
Dry ice is the solid form of carbon dioxide. It is commonly used for temporary refrigeration as CO2 does not have a liquid state at normal atmospheric pressure and Sublimation (phase transition), sublimes directly from the solid state to the gas state. It is used primarily as a cooling agent, but is also used in fog machines at theatres for dramatic effects. Its advantages include lower temperature than that of Ice, water ice and not leaving any residue (other than incidental frost from moisture in the atmosphere). It is useful for preserving frozen foods (such as ice cream) where Refrigeration, mechanical cooling is unavailable. Dry ice sublimes at at Earth atmospheric pressure. This extreme cold makes the solid dangerous to handle without protection from frostbite injury. While generally not very toxic, the outgassing from it can cause hypercapnia (abnormally elevated carbon dioxide levels in the blood) due to a buildup in confined locations. Properties Dry ice is the soli ...
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Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea in the south. The Japanese archipelago consists of four major islands—Hokkaido, Honshu, Shikoku, and Kyushu—and List of islands of Japan, thousands of smaller islands, covering . Japan has a population of over 123 million as of 2025, making it the List of countries and dependencies by population, eleventh-most populous country. The capital of Japan and List of cities in Japan, its largest city is Tokyo; the Greater Tokyo Area is the List of largest cities, largest metropolitan area in the world, with more than 37 million inhabitants as of 2024. Japan is divided into 47 Prefectures of Japan, administrative prefectures and List of regions of Japan, eight traditional regions. About three-quarters of Geography of Japan, the countr ...
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Fukushima Daiichi Nuclear Power Plant
The is a disabled nuclear power plant located on a site in the towns of Ōkuma, Fukushima, Ōkuma and Futaba, Fukushima, Futaba in Fukushima Prefecture, Japan. The plant Fukushima Daiichi nuclear disaster, suffered major damage from the 2011 Tōhoku earthquake and tsunami, magnitude 9.1 earthquake and tsunami that hit Japan on March 11, 2011. The chain of events caused radiation leaks and permanently damaged several of its reactors, making them impossible to restart. The working reactors were not restarted after the events. First commissioned in 1971, the plant consists of six boiling water reactors. These light water reactors drove electrical generators with a combined power of 4.7 GWe, making Fukushima Daiichi one of the 15 largest List of nuclear power stations, nuclear power stations in the world. Fukushima was the first nuclear plant to be designed, constructed, and run in conjunction with General Electric and Tokyo Electric Power Company (TEPCO). The sister n ...
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Boston
Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeastern United States. It has an area of and a population of 675,647 as of the 2020 United States census, 2020 census, making it the third-largest city in the Northeastern United States after New York City and Philadelphia. The larger Greater Boston metropolitan statistical area has a population of 4.9 million as of 2023, making it the largest metropolitan area in New England and the Metropolitan statistical area, eleventh-largest in the United States. Boston was founded on Shawmut Peninsula in 1630 by English Puritans, Puritan settlers, who named the city after the market town of Boston, Lincolnshire in England. During the American Revolution and American Revolutionary War, Revolutionary War, Boston was home to several seminal events, incl ...
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Big Dig
The Big Dig was a megaproject in Boston that rerouted the then elevated Central Artery of Interstate 93 that cut across Boston into the O'Neill Tunnel and built the Ted Williams Tunnel to extend Massachusetts Turnpike, Interstate 90 to Logan International Airport. Those two projects were the origin of the official name, the Central Artery/Tunnel Project (CA/T Project). The project constructed the Leonard P. Zakim Bunker Hill Memorial Bridge, Zakim Bunker Hill Bridge over the Charles River, created the Rose Fitzgerald Kennedy Greenway, Rose Kennedy Greenway in the space vacated by the previous I-93 elevated roadway, and funded more than a dozen projects to improve the region's public transportation system. Planning for the project began in 1982. Construction work was carried out between 1991 and 2006. The project concluded in December 2007. The project's general contractor was Bechtel, with Parsons Brinckerhoff as the engineers, who worked as a consortium, both overseen by the Ma ...
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Pykrete
Pykrete (, ) is a frozen ice composite, originally made of approximately 14% sawdust or some other form of wood pulp (such as paper) and 86% ice by weight (6 to 1 by weight). During World War II, Geoffrey Pyke proposed it as a candidate material for a supersized aircraft carrier for the British Royal Navy. Pykrete features unusual properties, including a relatively slow melting rate due to its low thermal conductivity, as well as a vastly improved strength and toughness compared to ordinary ice. These physical properties can make the material comparable to concrete, as long as the material is kept frozen. Pykrete is slightly more difficult to form than concrete, as it expands during the freezing process. However, it can be repaired and maintained using seawater as a raw material. The mixture can be moulded into any shape and frozen, and it will be tough and durable, as long as it is kept at or below freezing temperature. Resistance to gradual creep or sagging is improved by ...
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The Linde Group
Linde is a global Multinational corporation, multinational chemical company and the world's largest industrial gas supplier by market share and revenue. Founded by German scientist and engineer Carl von Linde in 1879 in Wiesbaden, Germany, the company is now headquartered in Woking, United Kingdom, and registered in Ireland as Linde plc. Linde plc was formed in 2018 through the merger of Linde AG and Praxair, which was founded in 1907 in the United States as Linde Air Products Company. The company's primary business is the manufacturing and distribution of atmospheric gases, including oxygen, nitrogen, argon, rare gases, and process gases, including carbon dioxide, helium, hydrogen, ammonia, electronic gases, specialty gases, and acetylene. Linde's products are used in the healthcare, petroleum refining, manufacturing, food, beverage carbonation, fiber-optics, steel making, aerospace, material handling equipment (MHE), chemicals, electronics and water treatment industries. Lin ...
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US Department Of Transport
The United States Department of Transportation (USDOT or DOT) is one of the executive departments of the U.S. federal government. It is headed by the secretary of transportation, who reports directly to the president of the United States and is a member of the president's Cabinet. The department's fiscal year 2022–2026 strategic plan states that its mission is "to deliver the world's leading transportation system, serving the American people and economy through the safe, efficient, sustainable, and equitable movement of people and goods." History In 1965, Najeeb Halaby, was granted authority over aviation and railroads through the commerce clause of the Constitution, the Federal Highway Administration and Federal Transit Administration primarily provided funding for state and local projects, without significant influence over road construction and operation. Halaby emphasized the need for improved coordination and expressed frustration at the lack of an overall plan. "One ...
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