The California Department of Transportation (Caltrans) is an executive department of the US state of California. The department is part of the cabinet-level California State Transportation Agency (CalSTA). Caltrans is headquartered in Sacramento.
The San Francisco–Oakland Bay Bridge, known locally as the Bay Bridge or as the Emperor Norton Bridge, is a complex of bridges spanning San Francisco Bay in California. As part of Interstate 80 and the direct road between San Francisco and Oakland, it carries about 260,000 vehicles a day on its two decks. It has one of the longest spans in the United States.
The 1989 Loma Prieta earthquake occurred on California’s Central Coast on October 17 at 5:04 p.m. local time. The shock was centered in The Forest of Nisene Marks State Park approximately 10 mi (16 km) northeast of Santa Cruz on a section of the San Andreas Fault System and was named for the nearby Loma Prieta Peak in the Santa Cruz Mountains. With an magnitude of 6.9 and a maximum Modified Mercalli intensity of IX (Violent), the shock was responsible for 63 deaths and 3,757 injuries. The Loma Prieta segment of the San Andreas Fault System had been relatively inactive since the 1906 San Francisco earthquake until two moderate foreshocks occurred in June 1988 and again in August 1989.
Structural engineers analyze, design, plan, and research structural components and structural systems to achieve design goals and ensure the safety and comfort of users or occupants. Their work takes account mainly of safety, technical, economic and environmental concerns, but they may also consider aesthetic and social factors.
Interstate 880 (I-880) is a major north–south auxiliary Interstate Highway in the San Francisco Bay Area of Northern California. It runs from I-280 and State Route 17 (SR 17) in San Jose to I-80 and I-580 in Oakland, running parallel to the eastern shore of San Francisco Bay. For most of its route, I-880 is officially known as the Nimitz Freeway, after World War II fleet admiral Chester Nimitz, who retired to the Bay Area and lived on Yerba Buena Island. The northernmost five miles is also commonly referred to as the Cypress Freeway, after the former alignment of the freeway, and its subsequent replacement.
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 San Diego–Coronado Bridge, locally referred to as the Coronado Bridge, is a prestressed concrete/steel girder bridge, crossing over San Diego Bay in the United States, linking San Diego with Coronado, California. The bridge is signed as part of State Route 75.
The Carquinez Bridge is a pair of parallel bridges spanning the Carquinez Strait at the northeastern end of San Francisco Bay. They form the part of Interstate 80 between Crockett and Vallejo, California. The name Carquinez Bridge originally referred to a single cantilever bridge built in 1927, which was part of the direct route between San Francisco and Sacramento. A second parallel cantilever bridge was completed in 1958 to deal with the increased traffic. Later, seismic problems made the 1927 span unsafe in case of an earthquake, and led to the construction, and 2003 opening, of a replacement: a suspension bridge officially named the Alfred Zampa Memorial Bridge, in memory of iron worker Al Zampa, who played an integral role in the construction of numerous San Francisco Bay Area bridges. The Alfred Zampa Memorial Bridge carries westbound traffic from Vallejo to Crockett, and the 1958 cantilever span carries eastbound traffic.
The MacArthur Maze is a large freeway interchange near the east end of the San Francisco–Oakland Bay Bridge in Oakland, California. It splits Bay Bridge traffic into three freeways—the Eastshore (I-80/I-580), MacArthur (I-580) and Nimitz (I-880).
The eastern span replacement of the San Francisco–Oakland Bay Bridge was a construction project to replace a seismically unsound portion of the Bay Bridge with a new self-anchored suspension bridge (SAS) and a pair of viaducts. The bridge is in the U.S. state of California and crosses the San Francisco Bay between Yerba Buena Island and Oakland. It was built between 2002 and 2013 and does not have a name other than the unofficial name of the bridge as a whole. The eastern span replacement is the most expensive public works project in California history, with a final price tag of $6.5 billion, a 2,500% cost overrun from the original estimate of $250 million. Originally scheduled to open in 2007, several problems delayed the opening until September 2, 2013. With a width of 258.33 ft (78.74 m), comprising 10 general-purpose lanes, it is the world's widest bridge according to Guinness World Records.
Earthquake engineering is an interdisciplinary branch of engineering that designs and analyzes structures, such as buildings and bridges, with earthquakes in mind. Its overall goal is to make such structures more resistant to earthquakes. An earthquake engineer aims to construct structures that will not be damaged in minor shaking and will avoid serious damage or collapse in a major earthquake. Earthquake engineering is the scientific field concerned with protecting society, the natural environment, and the man-made environment from earthquakes by limiting the seismic risk to socio-economically acceptable levels. Traditionally, it has been narrowly defined as the study of the behavior of structures and geo-structures subject to seismic loading; it is considered as a subset of structural engineering, geotechnical engineering, mechanical engineering, chemical engineering, applied physics, etc. However, the tremendous costs experienced in recent earthquakes have led to an expansion of its scope to encompass disciplines from the wider field of civil engineering, mechanical engineering, nuclear engineering, and from the social sciences, especially sociology, political science, economics, and finance.
The Cypress Street Viaduct, often referred to as the Cypress Structure or the Cypress Freeway, was a 1.6-mile-long, raised two-deck, multi-lane freeway constructed of reinforced concrete that was originally part of the Nimitz Freeway in Oakland, California.
T. Y. Lin International (TYLI) is a global, multi-disciplinary infrastructure services firm. Headquartered in San Francisco, TYLI established its business in the design of long-span bridges and specialty 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.
The James E. Roberts Memorial Bridge is a 1,400 foot two-lane highway bridge on California State Highway 120, in Tuolumne County, California. The bridge spans the Tuolumne River just north of Lake Don Pedro, near the community of Chinese Camp. It opened in 1971.
Harry Bolton Seed was an educator, scholar, former Professor at the University of California, Berkeley. He was regarded as the founding father of geotechnical earthquake engineering.
The San Mateo–Hayward Bridge is a bridge crossing the American state of California's San Francisco Bay, linking the San Francisco Peninsula with the East Bay. The bridge's western end is in Foster City, a suburb on the eastern edge of San Mateo. The eastern end of the bridge is in Hayward. It is the longest bridge in California and the 25th longest in the world by length. The bridge is owned by the state of California, and is maintained by California Department of Transportation (Caltrans), the state highway agency. Further oversight is provided by the Bay Area Toll Authority (BATA).
Michel Soto Chalhoub is a civil engineer who pioneered modern practice in shock, vibration, and seismic design using energy dissipating devices [ref]. He developed his methodologies while at the University of California, Berkeley, where he earned his Ph.D. in dynamics and seismic design.
Michael John Nigel Priestley was a New Zealand earthquake engineer. He made significant contributions to the design and retrofit of concrete structures, and developed the first displacement-based method of seismic design.
Medhat Haroun was an Egyptian-American expert on earthquake engineering. He wrote more than 300 technical papers and received the Charles Martin Duke Lifeline Earthquake Engineering Award (2006) and the Walter Huber Civil Engineering Research Prize (1992) from the American Society of Civil Engineers.
