Retrofit Vs. New Bridge

Retrofit Vs. New Bridge
Author: California. Transportation Economics Planning Program
Publisher:
Total Pages: 30
Release: 1997
Genre: San Francisco-Oakland Bay Bridge (Oakland and San Francisco, Calif.)
ISBN:

Two alternative projects were proposed to improve the safety of the motoring public on the east span of the San Francisco-Oakland Bay Bridge: retrofitting the existing bridge or building a new bridge parallel to it. To compare these two options from an economic and investment analysis point of view, a lifecycle/benefit-cost study was conducted to assess all benefits and costs of both options over the entire economic life of the bridge. Based on the lifecycle costs and benefits considered, and based on both agency and user costs, the new bridge would cost about $475 million (in discounted dollars) less than the retrofit option.

Seismic Design and Retrofit of Bridges

Seismic Design and Retrofit of Bridges
Author: M. J. N. Priestley
Publisher: John Wiley & Sons
Total Pages: 704
Release: 1996-04-12
Genre: Technology & Engineering
ISBN: 9780471579984

Because of their structural simplicity, bridges tend to beparticularly vulnerable to damage and even collapse when subjectedto earthquakes or other forms of seismic activity. Recentearthquakes, such as the ones in Kobe, Japan, and Oakland,California, have led to a heightened awareness of seismic risk andhave revolutionized bridge design and retrofit philosophies. In Seismic Design and Retrofit of Bridges, three of the world's topauthorities on the subject have collaborated to produce the mostexhaustive reference on seismic bridge design currently available.Following a detailed examination of the seismic effects of actualearthquakes on local area bridges, the authors demonstrate designstrategies that will make these and similar structures optimallyresistant to the damaging effects of future seismicdisturbances. Relying heavily on worldwide research associated with recentquakes, Seismic Design and Retrofit of Bridges begins with anin-depth treatment of seismic design philosophy as it applies tobridges. The authors then describe the various geotechnicalconsiderations specific to bridge design, such as soil-structureinteraction and traveling wave effects. Subsequent chapters coverconceptual and actual design of various bridge superstructures, andmodeling and analysis of these structures. As the basis for their design strategies, the authors' focus is onthe widely accepted capacity design approach, in which particularlyvulnerable locations of potentially inelastic flexural deformationare identified and strengthened to accommodate a greater degree ofstress. The text illustrates how accurate application of thecapacity design philosophy to the design of new bridges results instructures that can be expected to survive most earthquakes withonly minor, repairable damage. Because the majority of today's bridges were built before thecapacity design approach was understood, the authors also devoteseveral chapters to the seismic assessment of existing bridges,with the aim of designing and implementing retrofit measures toprotect them against the damaging effects of future earthquakes.These retrofitting techniques, though not considered appropriate inthe design of new bridges, are given considerable emphasis, sincethey currently offer the best solution for the preservation ofthese vital and often historically valued thoroughfares. Practical and applications-oriented, Seismic Design and Retrofit ofBridges is enhanced with over 300 photos and line drawings toillustrate key concepts and detailed design procedures. As the onlytext currently available on the vital topic of seismic bridgedesign, it provides an indispensable reference for civil,structural, and geotechnical engineers, as well as students inrelated engineering courses. A state-of-the-art text on earthquake-proof design and retrofit ofbridges Seismic Design and Retrofit of Bridges fills the urgent need for acomprehensive and up-to-date text on seismic-ally resistant bridgedesign. The authors, all recognized leaders in the field,systematically cover all aspects of bridge design related toseismic resistance for both new and existing bridges. * A complete overview of current design philosophy for bridges,with related seismic and geotechnical considerations * Coverage of conceptual design constraints and their relationshipto current design alternatives * Modeling and analysis of bridge structures * An exhaustive look at common building materials and theirresponse to seismic activity * A hands-on approach to the capacity design process * Use of isolation and dissipation devices in bridge design * Important coverage of seismic assessment and retrofit design ofexisting bridges

Remaking the San Francisco-Oakland Bay Bridge

Remaking the San Francisco-Oakland Bay Bridge
Author: Karen Trapenberg Frick
Publisher: Routledge
Total Pages: 240
Release: 2015-08-14
Genre: Architecture
ISBN: 1317338502

Winner of TransportiCA’s September Book Club Award 2018 On 17 October 1989 one the largest earthquakes to occur in California since the San Francisco earthquake of April 1906 struck Northern California. Damage was extensive, none more so than the partial collapse of the San Francisco–Oakland Bay Bridge’s eastern span, a vital link used by hundreds of thousands of Californians every day. The bridge was closed for a month for repairs and then reopened to traffic. But what ensued over the next 25 years is the extraordinary story that Karen Trapenberg Frick tells here. It is a cautionary tale to which any governing authority embarking on a megaproject should pay heed. She describes the process by which the bridge was eventually replaced as an exercise in shadowboxing which pitted the combined talents and shortcomings, partnerships and jealousies, ingenuity and obtuseness, generosity and parsimony of the State’s and the region’s leading elected officials, engineers, architects and other members of the governing elites against a collectively imagined future catastrophe of unknown proportions. In so doing she highlights three key questions: If safety was the reason to replace the bridge, why did it take almost 25 years to do so? How did an original estimate of $250 million in 1995 soar to $6.5 billion by 2014? And why was such a complex design chosen? Her final chapter – part epilogue, part reflection – provides recommendations to improve megaproject delivery and design.

Seismic Bridge Design and Retrofit -- Structural Solutions

Seismic Bridge Design and Retrofit -- Structural Solutions
Author: fib Fédération internationale du béton. Task Group: Seismic design and assessment procedures for bridges
Publisher: FIB - Féd. Int. du Béton
Total Pages: 3
Release: 2007
Genre: Technology & Engineering
ISBN: 2883940797

Bridge structures can give the impression that they are rather simple structural systems, whose seismic responses can be easily predicted. On the contrary, however, many bridges did not perform well in recent earthquakes, showing a need for increased research to understand various potential problems and collapse mechanisms. Indeed, progress has been made lately in design and assessment procedures around the world, and consequently many practices have changed. In this context, the objective of fib Bulletin 39 is to present, discuss and critically compare structural solutions for bridge seismic design and retrofit that have been developed and are now used all over the world, ten years after the publication of the last comprehensive manual on the subject. It is the result of the work of an international team of experts that collaborated intensively for over three years. The first four chapters of the Bulletin present a regional review of design choices, compare and discuss international design practices, and indicate their relative merits and potential problems. Current developments are treated in the next three chapters, with particular emphasis on design for enhanced damage control, for spatial variation of ground motion and for fault crossing. The last part presents a summary of current issues related to existing bridges. Extensive technical developments have been taking place in the last two decades with the goal of making bridges an important transportation infrastructure with limited damage during earthquakes. Realising this goal depends on regional seismicity, transportation systems, seismic performance goals, local cultures, and a wide range of design and construction practices, which are presented and discussed in this Bulletin.