Mark Ketchum's Bridge Engineering Page

Mark Ketchum's
Bridge Engineering Page

Some bridges on which I have worked:

	Rama IX Bridge, Bangkok, Thailand OPAC, AES, and Kinemetrics were engaged in 2000 by the Expressway and Rapid Transit Authority of Thailand to inspect, instrument, and evaluate the Rama IX Bridge, a 450m span cable stayed bridge. Excessive vibration of the bridge has led to concerns about its fatigue life.

	Arroyo Cangrejillo Bridge, Andalgala, Catamarca, Argentina OPAC designed this 336 m (1100 ft) span bridge to cross a 90m (300ft) deep canyon. Its taut cables sag only about 7m or 1/48th of the span. After the cables were strung across the canyon, the grillage of steel floorbeams and stringers was erected, starting at one end. 92 of the 134 segments were completed when this photo was taken. The nominal erection rate was 8 to 10 segments/day. This bridge is featured on the February 1999 cover of Structural Engineering International, the Journal of the International Association for Bridge and Structural Engineering. See an image of the cover here, or read a draft of the article here.

	Berkeley I-80 Pedestrian Overcrossing, Berkeley, California OPAC designed a pedestrian overcrossing of the I-80 freeway for the City of Berkeley, California that is now under construction. The 95m span basket-handle arch span across the freeway consists of tubualr steel arch ribs supporting a lightweight concrete post-tensioned edge girder deck. Its color, texture, amenities, sloping ADA-compliant curved ramps, touchdown plaza, and landscaping are not shown. The City of Berkeley also maintains an I-80 Bicycle/Pedestrian Overcrossing Web Page with information on this project.

	Carquinez Strait Bridge OPAC was contracted by Caltrans to study designs for a new bridge to replace the 1927 truss. After studying various structural options with National Constructors Group, a suspension bridge was selected. It is now under construction, as designed by the De Leuw - OPAC - Steinman Joint Venture under Caltrans supervision. Read about the wind tunnel tests of this bridge, as well. Caltrans also maintains web pages concerning this bridge. So far I've found this one, this one, this one, and this one. Also - visit Ed Tannenbaum's Live Carquinez Webcam, now showing the old bridges and the construction site.

	Ruck-A-Chucky Bridge In 1977 I was on the design staff for the most famous bridge never built - to cross the Auburn Dam reservoir. Also see elevation and perspective views of the 1,300 ft span cable stayed structure. Read T.Y. Lin's and D. Allan Firmage's technical paper about the bridge here

	East Bay Crossing Replacement In 1996, under contract to Caltrans, J. Paul Silvestri and I developed a structural concept for replacing the existing double deck truss bridge. This concept prompted the State's decision to replace instead of retrofit.

	West Bay Crossing Seismic Study Under a 1993 Caltrans contract, OPAC evaluated the seismic vulnerability of these back-to-back suspension bridges across San Francisco Bay. Get a Zipped .avi movie of the bridge FE model in an 8+ earthquake here (384 k)

	Bay Bridge Recordation I served as structural consultant to Architect Hansen, Murakami, Eshima, Inc. on the Bay Bridge Recordation - the largest HABS/HAER (Historical American Building Survey / Historical American Engineering Record) documentary project since the program was established with the National Park Service in 1934. Frank Deras and Dennis Hill were project photographers. These off-site links take you to their photos and brief project description.

	Maysville Bridge Under a 1995 contract, OPAC was engaged by Michael Baker Jr. Inc. to evaluate their bridge design and establish its constructability.

	Ping Ding Bridge I supervised the design (Frank Drouillard did most of the work) of this 120 m long arch bridge near Taipei.

	St. Johns Bridge OPAC performed a seismic susceptibility assessment of this historic 1930 suspension bridge that spans the Wilamette River in Portland, Oregon, in 1995, for the Oregon Department of Transportation.

	Tacoma Narrows Bridge Arvid Grant, J.P. Singh, and OPAC performed a seismic evaluation and retrofit study of the 2nd Tacoma Narrows Bridge in 1995, for the Washington State Department of Transportation. In 2000, I was engaged by WSDOT to assist in the development of retrofit construction measures.

	Golden Gate Bridge Between 1989 and 1992, I was lead investigator and Project Manager on studies of the Golden Gate Bridge that addressed 1) feasibility of adding a rail transit system, 2) seismic vulnerability, 3) seismic retrofit strategy, and 4) retrofit criteria.

	Bi Tan Pedestrian Bridge outside Taipei, Taiwan This 135 meter span pedestrian suspension bridge with a post tensioned precast segmental deck will replace an existing suspension bridge that was built by the Japanese during their occupation.

	SR-182 Columbia River Bridge at Richland, Washington This 1950 ft long twin segmental bridge crossing - now known as the Lee Volpertest Bridge - carries SR 182/16 N&S across the Columbia River. It won a PCI design award in 1984. I was lead engineer for preliminary design and provided oversight to Washington State DOT staff in final design. Photo courtesy of WSDOT.

Some other bridge projects and issues:

	"Japan Bridge" Pedestrian Overcrossing, La Défense, Paris (1994) A very handsome 100m span steel arch pedestrian overcrossing in an urban setting, by Peter Rice and his team in RFR, with Kisho Kurokawa architect. RFR's web site is here, their feature on this bridge is here.

	Storebaelt Suspension Bridge (Denmark) This $806 million bridge, completed in 1998, has the world's second longest span at 1,624 meters. It is part of an 18-km road and rail link between east and west Denmark. Designed by COWI Consulting Engineers and Planners.

	Normandie Bridge The world's longest span cable stayed bridge (856m) when it was completed in 1994, at the mouth of the Seine. Now Tatara at Onomichi-Imabari Japan has a longer span (890m, 1999).

	Malpensa Airport Access Roadway Bridge (Milan, Italy) Access roads to the Milan airport sweep up from ground level to the departures floor across curved cable-stayed bridges. Each bridge has two 70m long spans, and a single central 40m high pier. Eight stay cables support the precast prestressed deck.

	Collapsed Bridges Page When reality doesn't go along with plans . . .

	Bridge Aerodynamics A technical paper that dispells some myths about resonance.

	Bridge Facility Naming Conventions Ever wonder ... What's an overpass, an underpass, a viaduct, a separation? So do I. Well, Caltrans has it figured out.

	Menai Strait Bridge (Wales) Built 1820 to 1826. Designed by Thomas Telford. 579 ft main span, 153 ft towers, 100 ft clearance to Strait.

	Ganter Bridge (Simplon Pass, Brig, Switzerland) Designed by Christian Menn, 174 m span, 150 m high.


This website has been selected as a featured site in Lightspan's StudyWeb® as "one of the best educational resources on the Web". It is in the Arts:Architecture:Buildings & Projects:Bridges sections.

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