Chen3 abstract this paper presents the various geotechnical issues considered during the seismic design of. The skyway structures design of the new san francisco. After the loma prieta quake, the bay bridge was deemed a ticking time bomb. The northridge earthquake brought another significant change in bridge design and retrofitting. Lrfd seismic bridge design, california example mark s. The quake caused the oakland side of the bridge to shift 7 in 18 cm to the east, and caused the bolts of. Ucsd structural engineers honored for contributions to new bay. The bridge is a designated lifeline a road guaranteed to be accessible to emergency relief efforts soon after an earthquake. A modern seismology study indicated that the hayward and san andreas faults, which the bridge is situated in between, can generate magnitude 7.
It is used routinely for all types of architectural bridges with slender or curved shapes, and especially where. The new eastern span of the bay bridge in san francisco is designed to go with the flow if a major earthquake strikes. The division of engineering services des is the lead project delivery organization for the design, construction, and oversight of bridge and other transportation structures. Pretty interesting to see the engineering that allows the bridge to twist and flex. San franciscooakland bay bridge east span seismic safety. The detailed design of the izmit bay suspension bridge is used as an example, and descriptions are given of the local models prepared during design as well as the used analysis software. Seismic assessment and strengthening of reinforced concrete structures.
Design of the new san francisco oakland bay bridge. Worked on various alternatives for the replacement structure of the existing bay bridge east crossing 30% submittal. Dismantling of the san franciscooakland bay bridge east main span. The existing bay bridge east span was designed for 10%g earthquake acceleration which was consistent with the 1930 uniform building code recommendations. The design, engineering and construction teams have met the challenge of making the bay bridge seismically resilient with cuttingedge innovations and enhancementssome never before used in bridge buildingthat are transforming the bridge into a stateoftheart engineering icon. The east spans of the san francisco oakland bay bridge were closed in 1989 when a 50ft portion collapsed due to the 7. The san franciscooakland bay bridge, known locally as the bay bridge, is a complex of. Bay area bridges bay bridge overview san franciscooakland bay bridge richmondsan rafael bridge san mateo bridge dumbarton bridge carquinez bridge. New bay bridge design deemed quake safe local news. Seismobuild is an innovative finite elements package for the seismic assessment and strengthening of reinforced concrete framed structures that is targeted to the design office.
Behaviour and seismic design of stiffeners for steel. Behaviour and seismic design of stiffeners for steel bridge tower legs and piers. The bridge configuration was taken from massachusetts avenue overcrossing of. The new bridge across san francisco bay, the largest of its kind ever built, must be able to sway to withstand a big earthquake and one is expected. San francisco bay area toll bridge seismic retrofit and regional measure 1 programs 2012 second quarter project progress. Advances in design software and construction materials. The existing bridge was not designed for the most basic no rcollapse seismic safety criteria that is typically employed in modern bridge design. San francisco bay area toll bridge seismic retrofit and. The design, engineering and construction teams have met the challenge of making the bay bridge seismically resilient with cuttingedge innovations and.
Seismic analysis of san francisco oakland bay bridge. For state bridges, a nontoll seismic retrofit program is used. The san franciscooakland bay bridge, known locally as the bay bridge, is a complex of bridges spanning san francisco bay in california. This libguide is designed to help guide high school students when researching and building bridge structures. To survive a quake, new bay bridge span will offer least. The loma prieta earthquake, also known as the quake of 89 and the world. The old bridge is at risk in large bay area earthquakes as was demonstrated during the 1989 loma prieta earthquake. The san franciscooakland bay bridge crossing was the longest.
Dual screen high resolution backgrounds 2009 is designed to fit across two screens. Each screen must be set to either 1280x1024 or 1440x900 with total image resolution 2560x1024 or 2880x900. Bay bridge design task force, engineering and design. The new eastern span of the san franciscooakland bay bridge was. During the 1989 loma prieta earthquake, a portion of the eastern sections upper. The seismicallyvulnerable san franciscooakland bay bridge east spans, which connect oakland to yerba buena island ybi, will be replaced with a dual, 3. For part 1 of this story, see the march 2011 story superstructure rising slated to open in late 20, the new eastern span of the san franciscooakland bay bridge is meant to do what the old one didnt. Learn how autodesk 3d design products were used to help retrofit the bay bridge, the largest engineering project in california history. Design criteria for the bay bridge require it to be operational within 24 hours after a major earthquake.
San franciscooakland bay bridge seismic safety projects program overview. It has one of the longest spans in the united states. The companys software is making a green impact on san francisco alone, from the new energyefficient california academy of sciences to the bay bridge seismic retrofit and presidios doyle. The jiaozhou bay bridge, which china claims to be the worlds longest, is now open.
Izmit bay bridge geotechnical challenges and innovative. The seismic retrofit of the san franciscooakland bay bridge is more than an upgrade to one of the countrys busiest bridges. Buckle the catastrophic collapse of the cypress street viaduct during the loma prieta earthquake of october 17, 1989 and the loss of spans in both the struve slough bridge and the san franciscooakland bay bridge has emphasized, very forcibly. Marwan nader, lead design engineer for the new eastern span of the bay bridge, discusses features that give the bridge the flexibility to. To construct the worlds toughest bridge built with seismic strength and staying powerengineers had to design it like a machines that moves. The bay bridge lies between the hayward and the san andreas faults which can generate magnitude 7. Rendering of the san franciscooakland bay bridge east span. San franciscooakland bay bridge east span seismic safety project overview. Errors and defects in the conceptual design cannot be compensated for in the following calculations and detailed design of the engineer. San francisco oakland bay bridge replacement structure phase i. Bay bridge made to withstand major earthquake sfgate. To one side, traffic streams towards oakland across the existing bay bridge.
The project is located in a zone of very difficult environmental conditions characterized by deep soil strata of essentially normally consolidated silty clays to depths in excess of 80 m, a high water depth 60 m and a very strong seismic design motion with a peak ground acceleration of 0. San francisco a seismic safety examination of plans for a new eastern span of the san franciscooakland bay bridge has determined that the state department of transportation is on. Izmit bay bridge software free download izmit bay bridge. A seismically correct conceptual design is furthermore necessary in order to achieve a good earthquake resistance without. Des is a comprehensive, multidisciplinary engineering organization committed to providing our clients with quality products and services in a timely manner. Global inhouse ibdas3d fe software 7sets of earthquake time histories, at each of the 4foundations. Modelling and pre design of steel and composite structures 19961999. Simulation of the newly opened bay bridge in san francisco in an earthquake. Bay bridge design task force engineering and design advisory panel process outline the objective of this process is provide a structure for the engineering and design advisory panel to develop its recommendations for the bay bridge design task force. Now, mounting revelations of construction problems are calling. Lusas bridge is used by engineers worldwide for all types of bridge analysis, design and load rating from simple slab deck bridges, steel trusses, integral bridges and bowstring arch bridges, through to box girder, movable, cable stayed and suspension bridges. 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. Portal is a software to be used for the design of steel structures.
The macarthur maze or simply the maze, also called the distribution structure is a large freeway interchange near the east end of the san franciscooakland bay bridge in oakland, california. Seismic engineers who designed the span used a variety of innovative techniques some borrowed from offshore construction to help make the bridge strong, yet flexible enough to withstand the. Replacing the earthquakevulnerable east span of the bay bridge is the biggest engineering project in california history. Performance criteria require that the bridge must be operational immediately following a 1500year return period earthquake from either of these two faults. Caltrans entertained bids and selected two semifinalist designs from. In 1981, caltrans seismic design specifications were updated again following publication of the. One lesson learned from the collapse of the newhall overpass at the interchange of interstate 5 and state route 14 was that during a strong earthquake, short columns cannot displace as much seismic force as adjacent taller columns and can fail. Seismic engineers who designed the span used a variety of innovative techniques some borrowed from offshore construction to help make the bridge strong, yet flexible enough to. The bay bridge is located between the hayward fault and the san andreas fault which are capable of producing magnitude 7. Mahan1 abstract the newly approved aashto guide specification for lrfd seismic bridge design referred to as lrfd seismic guide spec, july 2007, is greatly influenced by caltrans seismic design criteria. To construct the worlds toughest bridgebuilt with seismic strength and staying powerengineers had to design it like a machines that moves. Lrfd design of california bridges sheet 11 of job title bent design originator bob matthews date 10192007 job no.
How its seismic issues are resolved will affect millions of people in san francisco and the east bay when a major quake hits and the outside world tries to rush in to help. It splits bay bridge traffic into three freewaysthe eastshore i80i580, macarthur i580 and nimitz i880. Sfobb east span seismic safety project limits and existing span. The san franciscooakland bridge, better known as the bay bridge, was one of the longest and most expensive undertakings in recent memory in california. Under this bay bridge prooftest program, every type of structural element, designed to see. Looked into software modeling issues regarding pushover analysis.
San franciscos huge new quakeproof bridge new scientist. The seismic retrofit of the bay bridge includes numerous cuttingedge and stateoftheart features that makes the bridge more resilient during an earthquake. Seismic conceptual design of buildings basic principles. San franciscooakland bay bridge seismic safety projects.
Earthquake resilient structure is a new branch of the seismic structural design. The gallery bay bridge east span seismic safety project autodesk. Communicating how the worlds largest selfanchored suspension bridge would reshape the surrounding landscape, as well as individual lives, was crucial to the success of the project. But it takes more than length to make a great bridge. Seismic design of buildings worked examples worked examples presented at the workshop ec 8. The program requires as input a gis point dataset of earthquake locations containing strike, dip, and rake values for a nodal plane of each earthquake. The new structural system is not only capable of preventing from the structure failure so as to protect peoples. Suspension bay bridge 1, where buckling of the stiffened tower leg plates were observed and faster strength degradation.
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