Three rivers - the Allegheny, Monongahela, and Ohio - join in Pittsburgh, making the city a natural site for the building of bridges. But the Smithfield Street Bridge stands apart from other Pittsburgh bridges for several reasons: it replaced structures by two well-known bridge engineers, Lewis Wernwag and John A. Roebling; it was the first use in America of the lenticular - or lens-shaped - truss design; and it was one of the first major bridges in the U.S. built primarily with steel.
ASCE
Sewall's Bridge is a singular example of an era when wooden trestle bridges carried highway traffic across New England waterways. It is the earliest pile-trestle bridge for which an authentic construction record exists, and the oldest for which builder's drawings survive. Spanning the York River, it was named for Major Samuel Sewall, Jr., the civil engineer who designed and constructed it.
The Second Street Bridge is a simply ornamented, wrought-iron structure. It is 18 feet wide and spans 225 feet over the Kalamazoo River. It was built to replace a dilapidated wooden bridge that had served the area for nearly 50 years.
The bridge is anchored to fieldstone abutments on each shore, and the deck is composed of wood beams. Iron lattice work provides structural stability and iron finials on the end posts provide aesthetic appeal. It includes a wooden pedestrian walkway.
Traversing the Great Glen of the Scottish Highlands for 60 miles the Caledonian Canal connects the North Sea by Beauly and Moray Firth on the east coast with the Irish Sea by Lochs Linnhe and Eil on the west. Thirty eight miles of the canal pass through freshwater lochs Douchfour, Ness, Oich and Lochy with the remaining 22 miles formed by earth cutting. Initially 28 locks, and later 29, were required to reach the summit elevation of 106 feet at Loch Oich.
The Savannah city plan, whose execution began in 1733, is distinguished from those of previous colonial towns by the repeated pattern of connected neighborhoods, multiple squares, streets, and designed expansion into lands held by the city. It is unique in the history of urban planning in a number of aspects, not the least of which is that the squares allow for more open space in Savannah than any city layout in history.
Located at the northern tip of Michigan where Lake Superior, Lake Michigan, and Lake Huron join together, the Sault Ste. Marie Hydroelectric Power Complex was built to harness the hydroelectric potential of the 20-foot falls at the headwaters of the St. Marys (sic) River, the sole outlet of Lake Superior. A century after its construction, the plant remains the largest low-head hydroelectric facility in the United States. Today, the Sault Ste. Marie plant supplies electricity to area residents, especially those in the Upper Peninsula of Michigan.
The San Jacinto Monument commemorates the decisive 1836 battle near the banks of the Buffalo Bayou and the San Jacinto River that allowed Texas to win independence from Mexico. It is the world's tallest monument, rising 15 feet higher than the Washington Monument.
In 1936, Daughters and Sons of the Republic of Texas led lobbying efforts to allocate funds for a monument that would mark the importance of the Battle of San Jacinto. Ground was broken on April 21, 1936 - 100 years to the day after the victorious battle.
The Salginatobel Bridge, spanning the Salgina Valley ravine, is the earliest surviving three-hinged, hollow box arch bridge designed by Robert Maillart.
Designed to connect the Shenandoah National Park in Virginia and the Great Smokey Mountains National Park in North Carolina, the Blue Ridge Parkway was planned to provide pleasant motoring and to conserve and interpret the unique natural and cultural resources of the Southern Highlands. It was conceived also as a public works project to relieve unemployment in the Appalachian region during the Great Depression.
Innovations
Central Pacific Railroad served as the Western terminus of America's first transcontinental railroad, passing through the formidable Sierra Nevada Mountains. In all, 15 tunnels were blasted through solid granite.
Thousands of Chinese from Kwantung Province were recruited by Central…
Read MoreThe Triborough Bridge Project is a three-branched waterway crossing that connects Manhattan, the Bronx, and Queens at a junction of the East River and the Harlem River in New York City. The complex structure includes a suspension bridge from Wards Island to Queens, a vertical lift span from…
Read MoreThe Borden Base Line is a 39,009.73 feet (7.42 miles ) survey line through the State of Massachusetts. The line was the first project of its kind undertaken in America and its establishment was the key element for Massachusetts pioneering mandate to survey the entire state.
The…
Read MoreThe design of the Bollman Truss Bridge-patented in 1852 and one of the first to use iron exclusively in all essential structural elements-was critical in the rapid expansion of American railroads in the 19th century. Replacing wooden bridges, which were cumbersome to build and vulnerable to…
Read MoreThis majestic viaduct was built during the golden age of railroading. It was at the western end of a major readjustment in grade and alignment of the Erie-Lackawanna Railroad, and had double tracks to carry the trains across the valley of Tunkhannock Creek. The Hallstead cutoff (between Scranton…
Read MoreAccording to oral history, George Washington visited the canal diggings in 1792, and then again in 1794, while he was accompanying troops to suppress the Whiskey Rebellion in Western Pennsylvania.
The Union Canal Tunnel was a crucial structure allowing the connection of the eastern and…
Read MoreIn the early 1900s, Union Station was the hub of passenger railroad traffic in the central United States. It was one of the first stations to serve as a centralized terminal for multiple railroad lines. It originally served 22 rail lines; 13 from the east and nine from the west.
The…
Read MoreThe United States Capitol is among the most symbolically important and architecturally impressive buildings in the nation. Construction of the original Capitol began in 1793, but it has been through several additions and alterations. Over its lifetime, the Capitol building has been built, burnt…
Read MoreIn 1930, the U.S. Corps of Engineers was directed to complete an engineering survey of the Tennessee River to determine the feasibility of establishing complete river navigability. The resulting report recommended a series of nine main river dams and several tributary dams to allow for a minimum…
Read MoreThe bridge is 408 meters long and weighed approximately 1,500 metric tons when built. Originally supported by four columns, two more were added in later years to support the weight of heavier rail cars.
In the late 19th century, the Malleco River represented the border between the…
Read MoreThe plant began operation only twenty-six days after Thomas Edison's first steam plant began operating on Pearl Street in New York (NL 46). On September 30, 1882, an Edison "K" type dynamo produced electricity from a water-powered turbine to light three buildings (two paper mills and the H.J.…
Read MoreDesigned by David B. Steinman, of Robinson & Steinman, New York City, the Waldo-Hancock suspension Bridge is a significant example of Steinman's work. David Steinman is considered among the most important suspension bridge designers of the 20th century. He earned an engineering degree from…
Read MoreThe structure has two segments: an East Channel bridge consisting of four 175-foot spans and three 240-foot spans crossing from Harrisburg to City Island; and a West Channel bridge, consisting of seven 175-foot spans crossing from City Island to Wormleysburg.
With 15 truss spans totaling…
Read MoreIt is a large, imposing structure (over a dozen rooms and spacious halls) dominated by a four-story octagonal tower at one corner and a second shorter square tower at another corner containing tanks for potable and fire-fighting water supply.
The Ward House, named for its builder William…
Read MoreUpon its dedication in 1885, the Washington Monument was the tallest structure in the world. Begun in 1848 to honor George Washington, the structure wasn't completed for over 36 years. Construction and financing problems slowed progress and the Civil War halted it completely.
In 1876,…
Read MoreThe Watertown Arsenal was the first major engineering testing laboratory in America. It was created to store and manufacture cutting-edge military technology and weaponry. The United States Army Research and Materials Laboratory continued to use the site until 1989, employing soldiers and…
Read MoreThe steel dome stretches 200 feet in diameter and rises 100 feet at its top. To accommodate thermal expansion, the inverted bowl-shaped structure originally rested on rollers that sat on the flat tops of six-story columns
There was a time when Americans from the Eastern seaboard braved…
Read MoreThe Whipple Bowstring Truss Bridge was built from a design patented in 1841 by Squire Whipple. Whipple was the first person to understand the stresses in truss members and he developed the first theoretical formula to calculate stresses in the articulated truss. His bowstring truss was the first…
Read MoreCombining British financing, American engineering, and Canadian contracting, the White Pass and Yukon was the first major civil engineering project on the continent above the 60th degree of northern latitude. Completed in 27 months using only hand tools, black powder, and regional timber, the…
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