Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. With better understanding of seismic demand on structures and with our recent experiences with large earthquakes near urban centers, the need of seismic retrofitting is well acknowledged. Prior to the introduction of modern seismic codes in the late 1960s for developed countries and late 1970s for many other parts of the world, many structures were designed without adequate detailing and reinforcement for seismic protection. In view of the imminent problem, various research work has been carried out. State-of-the-art technical guidelines for seismic assessment, retrofit and rehabilitation have been published around the world – such as the ASCE-SEI 41 and the New Zealand Society for Earthquake Engineering (NZSEE)'s guidelines. These codes must be regularly updated; the 1994 Northridge earthquake brought to light the brittleness of welded steel frames, for example.
The Ingalls Building, built in 1903 in Cincinnati, Ohio, is the world's first reinforced concrete skyscraper. The 16-story building was designed by the Cincinnati architectural firm Elzner & Anderson and was named for its primary financial investor, Melville E. Ingalls. The building was considered a daring engineering feat at the time, but its success contributed to the acceptance of concrete construction in high-rise buildings in the United States. It was converted to a hotel, the Courtyard by Marriott Cincinnati Downtown, in 2021.
A concrete slab is a common structural element of modern buildings, consisting of a flat, horizontal surface made of cast concrete. Steel-reinforced slabs, typically between 100 and 500 mm thick, are most often used to construct floors and ceilings, while thinner mud slabs may be used for exterior paving (see below).
Robert Maillart was a Swiss civil engineer who revolutionized the use of structural reinforced concrete with such designs as the three-hinged arch and the deck-stiffened arch for bridges, and the beamless floor slab and mushroom ceiling for industrial buildings. His Salginatobel (1929–1930) and Schwandbach (1933) bridges changed the aesthetics and engineering of bridge construction dramatically and influenced decades of architects and engineers after him. In 1991 the Salginatobel Bridge was declared an International Historic Civil Engineering Landmark by the American Society of Civil Engineers.
Claude Allen Porter Turner was an American structural engineer who designed a number of buildings and bridges, particularly in the midwestern U.S. states of Iowa, Minnesota, and Wisconsin.
Tunkhannock Creek Viaduct is a concrete deck arch bridge on the Nicholson Cutoff rail segment of the Norfolk Southern Railway Sunbury Line that spans Tunkhannock Creek in Nicholson, Pennsylvania, in the United States. Measuring 2,375 feet (724 m) long and towering 240 feet (73.15 m) when measured from the creek bed, it was the largest concrete structure in the world when completed in 1915 and still merited "the title of largest concrete bridge in America, if not the world" 50 years later.
Dr. W. Gene Corley, P.E. was an American structural engineer and "preeminent expert on building collapse investigations and building codes." Corley was the Senior Vice President of CTLGroup from 1987 to 2013, where he led structural engineering projects, including numerous evaluations of buildings and structures damaged by earthquake, explosions, and from terrorist attacks. He led the investigation of structural performance of the Murrah Building following the Oklahoma City bombing in 1995, and the World Trade Center Building Performance Study in 2001-2002 following the September 11, 2001 attacks. He died on March 1, 2013. He was 77.
Pacific Park Plaza is a 30-story residential building located in Emeryville, California adjacent to Interstate 80. Standing at 96.9 m tall, Pacific Park Plaza is the tallest building in Emeryville, and the tallest in the San Francisco Bay Area outside of San Francisco and Oakland.
The applied element method (AEM) is a numerical analysis used in predicting the continuum and discrete behavior of structures. The modeling method in AEM adopts the concept of discrete cracking allowing it to automatically track structural collapse behavior passing through all stages of loading: elastic, crack initiation and propagation in tension-weak materials, reinforcement yield, element separation, element contact and collision, as well as collision with the ground and adjacent structures.
The Frederick W. Panhorst Bridge, more commonly known as the Russian Gulch Bridge, is a reinforced concrete open-spandrel deck arch bridge on California State Highway 1, spanning Russian Gulch Creek in Russian Gulch State Park, Mendocino County, California, United States. It is named after Frederick W. Panhorst, who served as the Chief of the Bridge Section of the California Division of Highways from 1931 to 1960.
Hugh Ralston Crawford (1876–1954), practiced both as an engineer and architect in Australia and the United States in the first half of the 20th century.
Dovers Building is a reinforced concrete building in Melbourne, Australia. Built in 1908 by architect and engineer, Hugh Ralston Crawford, Dovers Building is located at 7 Drewery Lane, Melbourne.
Arching or compressive membrane action (CMA) in reinforced concrete slabs occurs as a result of the great difference between the tensile and compressive strength of concrete. Cracking of the concrete causes a migration of the neutral axis which is accompanied by in-plane expansion of the slab at its boundaries. If this natural tendency to expand is restrained, the development of arching action enhances the strength of the slab. The term arching action is normally used to describe the arching phenomenon in one-way spanning slabs and compressive membrane action is normally used to describe the arching phenomenon in two-way spanning slabs.
Kolbjørn Saether P.E., M.ASCE was an accomplished structural engineer in the City of Chicago for 47 years. Saether dedicated his life to engineering and was known as a leader in his field. He was a past director of the Structural Engineers Association of Illinois and was the organization's president from 1980 to 1981. During his career he developed innovative engineering solutions for skyrise building construction that are now part of the Chicago skyline, published theoretical insights to enhance the state of the art in structural engineering, and patented novel techniques to advance the art of building construction.
The Journal of Structural Engineering is the principal professional peer-reviewed journal of the American Society of Civil Engineers, the oldest professional civil engineering society in the United States. The journal is one of the flagship journals of the Society. It is sponsored by its division, the ASCE Structural Engineering Institute.
The Mersey Match Factory, later known as The Matchworks, is a former match factory on Speke Road, Garston, Liverpool, England. The factory closed in 1994, and has since been converted into offices and workshops. It had opened in 1921, having been built for Maguire, Paterson and Palmer, and later used by Bryant and May. The factory was the first building in the United Kingdom to be constructed using the flat-slab concrete technique. It is recorded in the National Heritage List for England as a designated Grade II listed building.
Ahsan Kareem is the Robert M. Moran Professor of Engineering in the Department of Civil & Environmental Engineering and Earth Sciences (CEEES) at the University of Notre Dame. He is Director of the Nathaz Modeling Laboratory and served as the past Chair at the Department of CEEES at the University of Notre Dame.
A waffle slab or two-way joist slab is a concrete slab made of reinforced concrete with concrete ribs running in two directions on its underside. The name waffle comes from the grid pattern created by the reinforcing ribs. Waffle slabs are preferred for spans greater than 40 feet (12 m), as they are much stronger than flat slabs, flat slabs with drop panels, two-way slabs, one-way slabs, and one-way joist slabs.
Michael C. Constantinou is an American structural engineer who is a Samuel P. Capen Professor and State University of New York Distinguished Professor in the Department of Civil, Structural and Environmental Engineering at the University at Buffalo. He also serves an editor of the Journal of Earthquake Engineering and Structural Dynamics
Andrew Stuart Whittaker is an American structural engineer who is currently a SUNY Distinguished Professor in the Department of Civil, Structural and Environmental Engineering at the University at Buffalo, State University of New York.
