Presentation on theme: "SHRP2 Project R04 Bridge Designs for ABC"— Presentation transcript:
1SHRP2 Project R04 Bridge Designs for ABC FHWA P2P ExchangeAug BostonSHRP2 Project R04 Bridge Designs for ABC Bala SivakumarHNTB Corp.
2SHRP2 Project R04 PROJECT GOAL To develop standardized approaches to designing, constructing, and reusing complete bridge systems that address rapid renewal needsPhase I – Define ABC ChallengesPhase II – Identify & Refine the Best ABC TechnologiesPhases III & IV – Standardize & Deploy ABCPhase V – Beta testing of ABC Toolkit by VAOT
3INNOVATIVE BRIDGE DESIGNS FOR RAPID RENEWAL SHRP2 Project R04INNOVATIVE BRIDGE DESIGNS FOR RAPID RENEWALHNTB (Prime)Iowa State UniversityStructural Engineering Assoc.Genesis StructuresDr Monica Starnes, Senior Program Officer SHRP2
4ABC ELEMENTS & METHODS Accelerated Bridge Construction (ABC) Prefabricated ElementsPrefabricated Modular SystemsStructure Placement MethodsAccelerated Geo-tech WorkABC ELEMENTS & METHODSSHRP2 R04 -- Phases I, II, III(2008 – 2011)Phase IV ( )
5SHRP2 R04 ABC Toolkit 1 2 3 4 5 ABC STANDARD DESIGN CONCEPTS ABC ERECTION CONCEPTS3ABC SAMPLE DESIGN CALCULATIONS4ABC DESIGN SPECIFICATIONS (LRFD)5ABC CONSTRUCTION SPECIFICATIONSExpected Outcome: The designer, guided by the standard design concepts, details and the set of ABC design calculations will be better prepared to complete an ABC design for a routine bridge replacement project.
6ABC Standard Design Concepts GOALS:Focus on conventional bridgesComplete bridges using prefabricated elementsContractor could self-perform a lot of the workFabricate on site or in a plant and erect using conventional cranesFast assembly in the field in 1 to 2 weeks (Tier 3 or less)Durable connections / durable bridges
7Span Ranges for Superstructures Simple / continuous spans from 40 ft to 130 ft.Simple for DL ; Continuous for LL ; No Open JointsPlans are grouped in the following span ranges:40 ft to 70 ft70 ft to 100 ft100 ft to 130 ft.Spans to 130 ft can usually be transported and erected in one piece at many sites.Weight < 200 Kips for erection using conventional cranes commonly used by contractors
8Prefabricated Decked Beam Elements 2 Lane bridge with shoulders shown – customize width for siteDeck Bulb TeesDouble TeesModular Decked Beams
9Modular Decked Beams Barrier can be precast Barrier load on exterior module
10Prestressed Decked Girders Decked Bulb TeeSpan lengths from 40 ft to 130 ftUT, WA, ID among states with DBT standardsBased on the PCI NEXT beamSpans to 90 ftLow depth alternativeAdjacent Double Tee
11Prefabricated Substructure Elements ABUTMENTS & WINGWALLSSemi Integral AbutmentsIntegral AbutmentsInline or U type WingwallsSupported on Piles and Spread FootingsPIERSPrecast Conventional PierPrecast Straddle BentDrilled Shaft and Spread Footing Options
12Integral and Semi-Integral Bridges for Rapid Renewal Well suited for ABCThey allow the joints to be moved beyond the bridgeClose tolerances required when utilizing expansion bearings and joints are eliminatedThe backwall is precast with the deck.Fast erection in 1 to 2 days, economical
13Semi-Integral Abutment Suspended Backwall H piles or spread footingsFill pile pockets with SCCEasy fit-up in the field
14Precast PiersNon-prestressed so contractor can self- perform precastingFast erection using grouted splice couplersConventional PierDeep foundation may be outside existing footprintStraddle Bent
15ABC Connections Connections affect field assembly time. Goal is rapid field assembly and long-term durability of jointsAlso, flexural continuity between modules to emulate CIP constructionConnections affect seismic performanceREFERENCE: FHWA Connections Manual
16Connections for ABCUltra High Performance Concrete (UHPC) longitudinal & transverse joints between superstructure modulesGrouted splice couplers in piers replace the typical lap spliceSelf Consolidating Concrete (SCC) pile connections and abutment to wingwall connections……………………………………………………………………………………Grouted cap pockets / grouted ducts for substructure connections (seismic)Other rapid set concrete options may be used
18UHPC Joints in Bridge Deck Allows rapid construction. No post tensioning requiredUHPC joints are typically 6 in wide. Good durabilityCan be reinforced with hairpin bars or straight bars(Longitudinal Joint.Longitudinal steel not shown)
19Erection Concepts for Prefabricated Elements Erection Concept DrawingsErection using conventional cranes.Erection using ABC construction technologies adapted from long span construction
20Erection Concepts for Bridge Replacement Using Cranes Short Single Span over Stream Cranes selected for 90 Kip pickLonger Span over RoadwayWeight up to 200 kips
21Erection with ABC Construction Technologies Use ABC construction technologies where ground access for cranes below the bridge may be limited.Conventional cranes with enough reachABC technologies that allow construction from above:Above Deck Driven CarriersLaunched Temporary BridgeTransverse Gantry FramesLongitudinal Gantry Frames
22Above Deck Driven Carriers Allows fast rate of erectionRides on existing bridge, new bridge (check capacity to support)Ideal for bridges with many spans. long viaducts
23Launched Temporary Bridge Sites with limited ground access or long spansLaunched across or lifted over a span to act as a “temporary bridge”Used to deliver the heavier modules without inducing large erection stresses.Temp bridge can also support transverse gantry frames
25ABC Design Specifications for LRFD The LRFD Design Specifications do not explicitly deal with the unique aspects of large scale prefabricationIn some cases, the most extreme load case may occur during shipping and handling.The work in SHRP2 R04 entailed the identification of any shortcomings in the current LRFD Bridge Design SpecificationsRecommendations are provided for addressing these limitations.
26ABC Sample Design Calculations Three ABC design examples for prefabricated systems in the toolkit:Modular Decked BeamsDecked Precast Prestressed GirderPrecast PierDesign Criteria:AASHTO LRFD (5th Edition)Supplemental ABC criteriaThe design examples provide guidance on the overall structural design of bridge components for ABC
27LRFD for ABC DesignThe design of most ABC elements and systems follows traditional LRFD design specifications.Design the ABC elements and the completed structure using all applicable LRFD Limit StatesAdditional requirements apply for ABC connections, lifting and moving of prefabricated elements and modules.
28Decked Steel Girder Design for ABC Three Stages for DesignPrefabrication Stage (many support options)Load Case 1 = Dead load on module steel section onlyLoad Case 2 = Dead load on module composite sectionErection Stage (many lift options)Load Case 3 = Modules are lifted into placeFinal StageLoad Case 4 = Modules are assembled and made continuousDLFWSLL + IMUtilities
29ABC Construction Specifications Recommended Special Requirements for ABCFocus heavily on means and methods requirements for rapid construction.Proposed Section in LRFD Construction SpecificationsXX.1 GENERALXX.2 RESPONSIBILITIESXX.3 MATERIALSXX.4 FABRICATIONXX.5 SUBMITTALSXX.6 QUALITY ASSURANCEXX.7 Handling, Storing, and TransportationXX.8 Geometry ControlXX.9 ConnectionsXX.10 ERECTION METHODSXX.11 ERECTION PROCEDURES
30First Demonstration Project Demonstrate Use of ABC Concepts Developed in SHRP2 R04 Keg Creek Bridge, IowaTotal prefabricated bridgeABC design concepts & details developed in SHRP2 R04 Project were used with minimal customization for the site14 day ABC periodOpened Nov 1, 2011
32Closing The time for ABC is now New generation PBES for ABC are economical to construct and designed for durabilitySHRP2 R04 ABC Toolkit and training materials will be available to provide guidance to those new to ABC and the use of PBESSHRP2 R04 demonstration projects showcase the use of the ToolkitSHRP2 R04 ABC Toolkit to be available soonThe time for ABC is now