ASPIRE Summer 08 - Aspire - The Concrete Bridge Magazine

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The site geometry called for a bridge to span the roadwayand provide access to the parking structure.The tall, slender piers supported on singledrilled shafts performed well when analyzed forseismic loading.Any change in natural conditions of thehighly plastic shaley clays could leadto instability. Drilled shaft foundationswere designed for an additional 40kips of lateral load, in addition to otherlateral loads on the piers, as a result ofpotential slope creep in the 45-ft-thicksoil mass overlying the limestonebedrock. Drilled shafts were socketed2.5 diameters into the limestone belowthe fill to provide additional lateralThe substructure consists of single pierson single drilled shafts.resistance. Since falsework and shoringwere used to build the new structure,recommendations were also providedfor allowable bearing pressures forfalsework support footings.The bridge was built over a 10-monthperiod. Following installation ofthe drilled shafts and pier columns,the voided slab superstructure wasconstructed on falsework with concreteplaced in a sequential manner. Positivemoment sections were placed first,followed by 30-ft-long segments overthe pier supports. Forms were camberedto account for dead load deflections andremoved when the concrete strengthreached 3000 psi.The cast-in-place concrete bridgeprovided an economical and attractivesolution in this combined commercialand residential setting while the complexgeometry of the site and shallowstructure requirements made the castin-placeoption ideally suited for thisapplication._____________________________Kevin Eisenbeis is a principal withHarrington & Cortelyou Inc., Kansas City,Mo.For more information on this or otherprojects, visit www.aspirebridge.org.AESTHETICSCOMMENTARYby Frederick GottemoellerThis structure is an excellent resolutionof a complicated structural andaesthetic problem: the bridge with abranch. Designing a bridge like this withtypical steel or concrete I-beams alwaysresults in a confusion of beam layoutsand awkward connections. The cast-inplacevoided slab, on the other hand,adapts readily. All of the connections andpoints of force transfer are inside theslab. The exterior shows only a smoothcontinuous surface along the main linesof the structure. The bridge seems to beall one piece. The eye effortlessly followsits edges from abutment to abutment.The cross section of the superstructurealso has enough torsional stiffnessto allow single column supports. Thisminimizes the number of columns andallows streets, planting areas, and viewsto flow through under the bridge. Thespace under the bridge remains a pleasantplace to be. Finally, the flares at thetop of the columns make clear the flowof forces from the superstructure to theground. They make this small but complexstructure memorable.42 | ASPIRE, Summer 2008
Spikes in Worldwide Steel Prices ImpactBridge ConstructionWorldwide demand and the weak dollar have led to unprecedentedprice increases and volatility for all types of steelproducts. According to data published by American MetalMarket (AMM), steel plate prices increased 63% between Januaryand May 2008; high-strength wire rod used in the productionof prestressing strand increased 34%, and steel reinforcementincreased 48%.These increases pose major challenges for owners, contractors,and industry suppliers. Out-of-date estimates can result infunding shortfalls. Fixed price bids, which have not anticipatedthese sky-rocketing prices, threaten the financial viability of contractorsand suppliers alike. Owners, contractors, and suppliersare urged to work together to meet this challenge and reasonablymanage risk for all involved in bridge construction.On a positive note, as material prices continue to rise, theuse of high-strength materials generally becomes more costcompetitive. Prestressed concrete bridges that proportionally049_DSI_ADUS_178x117 20.12.2006 11:06 Uhr Seite 1use less steel are even more economical when compared toother structural systems.Post-tensioning is being utilized on bridges in increasinglyvaried ways, including cable stays for long-span applications,segmental construction, on bridge decks, strengthening, andon spliced girders to extend the capabilities of precast elements.Post-tensioning offers some unique advantages, whichcan reduce material usage and improve overall economy andperformance.PTI has training programs to improve the quality of post-tensionedconstruction. The Bonded Post-Tensioning Certificationprogram is a comprehensive course on all aspects of bondedpost-tensioning installation. The 3-day training workshopis intended for construction personnel, inspectors, and constructionmanagers. Attendees are certified following successfulcompletion of the training and the subsequent examination.For more information about post-tensioned bridgesand training programs, contact PTI or visit our website at:www.post-tensioning.org.DYWIDAGPost-Tensioning Systems Multistrand Post-Tensioning Systems Bar Post-Tensioning Systems DYNA Bond ® Stay Cable Systems DYNA Grip ® Stay Cable Systems Engineering Construction Methods Stay Cable Testing Supply and InstallationDYWIDAG-SYSTEMS INTERNATIONALHQ America Business Unit 525 Wanaque Avenue 4732 Stone Drive, Suite BPost-Tensioning & Reinforcement Pompton Lakes, NJ 07042, USA Tucker, GA 30084, USADYWIDAG-SYSTEMS Phone (973) 831-6560 Phone (770) 491-3790INTERNATIONAL USA INC.320 Marmon Drive320 Marmon Drive Bolingbrook, IL 60440, USA 1801 N. Peyco Drive 2154 South StreetBolingbrook, IL 60440, USA Phone (630) 739-1100 Arlington, TX 76001-6704, USA Long Beach, CA 90805, USAPhone (630) 739-1100 Phone (817) 465-3333 Phone (562) 531-6161Fax (630) 972-9604E-mail: dsiamerica@dsiamerica.com www.dsiamerica.comASPIRE, Summer 2008 | 43
Page 2: ®Bentley®LEAPBridge. It’s all i
Page 10: FOCUSPARSONS adapts to theMARKETby
Page 16 and 17: PERSPECTIVESustainableConcrete Brid
Page 18 and 19: PROJECTONE OF ELEVEN,BUT ONE OF A K
Page 20 and 21: WSDOT Moving TowardsPerformance-Bas
Page 22 and 23: Girders on the draw pontoons, where
Page 24 and 25: Replacement of the I-10 Bridgesacro
Page 26 and 27: Precast, prestressed concrete girde
Page 28 and 29: AvoidingLANDSLIDESby Kevin Harper,
Page 30 and 31: For both bridges, the piers were lo
Page 32 and 33: ECONOMICAL BRIDGEWIDENINGby Craig A
Page 34 and 35: Precast, prestressed concrete beams
Page 36 and 37: An artist’s rendering showsthe br
Page 39 and 40: Concrete for the main span wasdeliv
Page 41 and 42: Precast Span-by-SpanPrecast Balance
Page 43: A cast-in-placereinforced concreteb
Page 47 and 48: S A F E T Y AND S E R V I C E A B I
Page 49 and 50: The Methow River Bridge usesWSDOT
Page 51 and 52: American Coal Ash AssociationThe Ro
Page 53 and 54: Bridge MonitoringKnow more about yo
Page 56 and 57: Integrated 3D DesignParaBridge is a
Page 58 and 59: hood canal Bridge / WASHINGTONOnce
Page 60 and 61: I-10 Bridge Replacement / floridaPr
Page 62 and 63: I-10 Bridge Replacement / floridaTy
Page 64 and 65: I-10 Bridge Replacement / floridaLo
Page 66 and 67: South fork eel river Bridges / cali
Page 68 and 69: Photo: Michael Baker Jr. Inc.Pomero
Page 70 and 71: Pomeroy-Mason Bridge / WEST VIRGIni

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