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Ashtabula River Railroad Disaster
The Ashtabula River railroad disaster (also called the Ashtabula horror, the Ashtabula Bridge disaster, and the Ashtabula train disaster) was the failure of a bridge over the Ashtabula River near the town of Ashtabula, Ohio, in the United States on December 29, 1876. A Lake Shore and Michigan Southern Railway train, the Pacific Express, passed over the bridge as it failed. All but the lead locomotive plunged into the river. The train's oil lanterns and coal-fired heating stoves set the wooden cars alight. Firefighters declined to extinguish the flames, leaving individuals to try to pull survivors from the wreck. Many who survived the crash burned to death in the wreckage. The accident killed approximately 92 of the 160 people aboard. It was the worst rail accident in the U.S. in the 19th century and the worst rail accident in U.S. history until the Great Train Wreck of 1918. The coroner's report found that the bridge, located about from the railway station, had been improperl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harper's Weekly
''Harper's Weekly, A Journal of Civilization'' was an American political magazine based in New York City. Published by Harper & Brothers from 1857 until 1916, it featured foreign and domestic news, fiction, essays on many subjects, and humor, alongside illustrations. It carried extensive coverage of the American Civil War, including many illustrations of events from the war. During its most influential period, it was the forum of the political cartoonist Thomas Nast. History Inception Along with his brothers James, John, and Wesley, Fletcher Harper began the publishing company Harper & Brothers in 1825. Following the successful example of ''The Illustrated London News'', Harper started publishing ''Harper's Magazine'' in 1850. The monthly publication featured established authors such as Charles Dickens and William Makepeace Thackeray, and within several years, demand for the magazine was great enough to sustain a weekly edition.Palmquist & Kailborn 2002, p. 279. In 1857, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cast Iron
Cast iron is a class of iron– carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impurities which allow cracks to pass straight through, grey cast iron has graphite flakes which deflect a passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite "nodules" which stop the crack from further progressing. Carbon (C), ranging from 1.8 to 4 wt%, and silicon (Si), 1–3 wt%, are the main alloying elements of cast iron. Iron alloys with lower carbon content are known as steel. Cast iron tends to be brittle, except for malleable cast irons. With its relatively low melting point, good fluidity, castability, excellent machinability, resistance to deformation and wear resistance, cast irons have become an engineering material with a wide range of applications a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erie, Pennsylvania
Erie (; ) is a city on the south shore of Lake Erie and the county seat of Erie County, Pennsylvania, United States. Erie is the fifth largest city in Pennsylvania and the largest city in Northwestern Pennsylvania with a population of 94,831 at the 2020 census. The estimated population in 2021 had decreased to 93,928. The Erie metropolitan area, equivalent to all of Erie County, consists of 266,096 residents. The Erie-Meadville combined statistical area had a population of 369,331 at the 2010 census. Erie is roughly equidistant from Buffalo and Cleveland, each being about 100 miles (160 kilometers) away. Erie's manufacturing sector remains prominent in the local economy, though insurance, healthcare, higher education, technology, service industries, and tourism are emerging as significant economic drivers. As with the other Great Lakes port cities, Erie is accessible to the oceans via the Lake Ontario and St. Lawrence River network in Canada. The local climate is hu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snowdrift
A snowdrift is a deposit of snow sculpted by wind into a mound during a snowstorm. Snowdrifts resemble sand dunes and are formed in a similar manner, namely, by wind moving light snow and depositing it when the wind has virtually stopped, usually against a stationary object. Snow normally crests and slopes off toward the surface on the windward side of a large object. On the leeward side, areas near the object are a bit lower than surrounding areas, but are generally flatter. The impact of snowdrifts on transportation can be more significant than the snowfall itself, such as in the USA during the Great Blizzard of 1978. Snowdrifts are many times found at or on roads, as the crest of the roadbed or the furrows along the road create the disruption to the wind needed to shed its carried snow. Snow fences may be employed on the windward side of the road to intentionally create a drift before the snow-laden wind reaches the road. Photo gallery File:Long Mynd snowdrift.jpeg, S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blizzard
A blizzard is a severe snowstorm characterized by strong sustained winds and low visibility, lasting for a prolonged period of time—typically at least three or four hours. A ground blizzard is a weather condition where snow is not falling but loose snow on the ground is lifted and blown by strong winds. Blizzards can have an immense size and usually stretch to hundreds or thousands of kilometres. Definition and etymology In the United States, the National Weather Service defines a blizzard as a severe snow storm characterized by strong winds causing blowing snow that results in low visibilities. The difference between a blizzard and a snowstorm is the strength of the wind, not the amount of snow. To be a blizzard, a snow storm must have sustained winds or frequent gusts that are greater than or equal to with blowing or drifting snow which reduces visibility to or less and must last for a prolonged period of time—typically three hours or more. Environment Canada def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buffalo, New York
Buffalo is the second-largest city in the U.S. state of New York (behind only New York City) and the seat of Erie County. It is at the eastern end of Lake Erie, at the head of the Niagara River, and is across the Canadian border from Southern Ontario. With a population of 278,349 according to the 2020 census, Buffalo is the 78th-largest city in the United States. The city and nearby Niagara Falls together make up the two-county Buffalo–Niagara Falls Metropolitan Statistical Area (MSA), which had an estimated population of 1.1 million in 2020, making it the 49th largest MSA in the United States. Buffalo is in Western New York, which is the largest population and economic center between Boston and Cleveland. Before the 17th century, the region was inhabited by nomadic Paleo-Indians who were succeeded by the Neutral, Erie, and Iroquois nations. In the early 17th century, the French began to explore the region. In the 18th century, Iroquois land surrounding Buffalo C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ashtabula Bridge
Ashtabula ( ) is a city in Ashtabula County, Ohio, United States, and the center of the Ashtabula micropolitan area. It is located at the mouth of the Ashtabula River on Lake Erie, northeast of Cleveland. As of the 2020 census, the city had a total population of 17,975. Like many other cities in the Rust Belt, it has lost population due to a decline in industrial jobs since the 1960s. The name ''Ashtabula'' is derived from , which means 'always enough fish to be shared around' in the Lenape language. The city became an important destination on the Underground Railroad in the middle 19th century, as refugee slaves could take ships to Canada and freedom. Even in the free state of Ohio, they were at risk of being captured by slavecatchers. Beginning in the late 19th century, the city became a major coal port on Lake Erie at the mouth of the Ashtabula River northeast of Cleveland. Coal and iron were shipped here, the latter from the Mesabi Range in Minnesota. The city attra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bending
In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element. The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or less, of the other two.Boresi, A. P. and Schmidt, R. J. and Sidebottom, O. M., 1993, Advanced mechanics of materials, John Wiley and Sons, New York. When the length is considerably longer than the width and the thickness, the element is called a beam. For example, a closet rod sagging under the weight of clothes on clothes hangers is an example of a beam experiencing bending. On the other hand, a shell is a structure of any geometric form where the length and the width are of the same order of magnitude but the thickness of the structure (known as the 'wall') is considerably smaller. A large diameter, but thin-walled, short tube supported at its ends an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shim (spacer)
A shim is a thin and often tapered or wedged piece of material, used to fill small gaps or spaces between objects. Shims are typically used in order to support, adjust for better fit, or provide a level surface. Shims may also be used as spacers to fill gaps between parts subject to wear. Materials Many materials make suitable shim stock (also often styled shimstock), or base material, depending on the context: wood, stone, plastic, metal, or even paper (e.g., when used under a table leg to level the table surface). High quality shim stock can be bought commercially, for example as laminated shims, but shims are often created ad hoc from whatever material is immediately available. Laminated shim stock is stacked foil that can be peeled off one layer at a time to adjust the thickness of the shim. Applications In automobiles, shims are commonly used to adjust the clearance or space between two parts. For example, shims are inserted into or under bucket tappets to control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falsework
Falsework consists of temporary structures used in construction to support a permanent structure until its construction is sufficiently advanced to support itself. For arches, this is specifically called centering. Falsework includes temporary support structures for formwork used to mold concreteHardie G.M. (1995) Building Construction: Principles, Practices, and Materials. New Jersey: Prentice Hall. (Pg 116, paragraph 1) in the construction of buildings, bridges, and elevated roadways. The British Standards of practice for falsework, BS 5975:2008, defines falsework as "Any temporary structure used to support a permanent structure while it is not self-supporting." History Falsework has been employed in bridge and viaduct construction since ancient times. The Romans were renowned for its use, as at the Limyra Bridge in Turkey. Until the turn of the 20th century almost all falsework was constructed from timber. To compensate for timber shortages in different regions and to ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half Angle Block
One half ( : halves) is the irreducible fraction resulting from dividing one by two or the fraction resulting from dividing any number by its double. Multiplication by one half is equivalent to division by two, or "halving"; conversely, division by one half is equivalent to multiplication by two, or "doubling". One half often appears in mathematical equations, recipes, measurements, etc. Half can also be said to be one part of something divided into two equal parts. For instance, the area ''S'' of a triangle is computed. :''S'' = × perpendicular height. One half also figures in the formula for calculating figurate numbers, such as triangular numbers and pentagonal numbers: : \frac and in the formula for computing magic constants for magic squares : M_2(n) = \frac \left(n^ + 1\right) The Riemann hypothesis states that every nontrivial complex root of the Riemann zeta function has a real part equal to . One half has two different decimal expansion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Stress
Shear stress, often denoted by (Greek: tau), is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. ''Normal stress'', on the other hand, arises from the force vector component perpendicular to the material cross section on which it acts. General shear stress The formula to calculate average shear stress is force per unit area.: : \tau = , where: : = the shear stress; : = the force applied; : = the cross-sectional area of material with area parallel to the applied force vector. Other forms Wall shear stress Wall shear stress expresses the retarding force (per unit area) from a wall in the layers of a fluid flowing next to the wall. It is defined as: \tau_w:=\mu\left(\frac\right)_ Where \mu is the dynamic viscosity, u the flow velocity and y the distance from the wall. It is used, for example, in the description of arterial blood flow in which case which t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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