Folded Plate Bridge: Steel Folded Plate Bridge: Steel Alternative for Short Span BridgesAlternative for Short Span Bridges

Maury TayaraniMaury TayaraniAccelerated Bridge Program Accelerated Bridge Program

MassDOTMassDOT

Folded Plate Girder System is Folded Plate Girder System is currently applicable to simple span currently applicable to simple span

bridges with lengths up to 60 ft.bridges with lengths up to 60 ft.

Folded Plate Girders are fabricated Folded Plate Girders are fabricated using press breaksusing press breaks

The bend locations are very precisely determinedThe bend locations are very precisely determined

The fabrication process requires rotating the The fabrication process requires rotating the girdergirder

Fabrication Steps are MinimalFabrication Steps are Minimal

1- Bending girders1- Bending girders2- End Plates2- End Plates3- Minimal Tie Plates3- Minimal Tie Plates4- Shear Studs4- Shear Studs

11

33

22 44

To Resolve Availability and To Resolve Availability and Rapid DeliveryRapid Delivery

1- 1- Plate thicknesses are limited to ½ or 3/8 inchesPlate thicknesses are limited to ½ or 3/8 inches

2- Total plate width is limited to 118 inches2- Total plate width is limited to 118 inches

Stable Shape During Casting DeckStable Shape During Casting Deck

No need for internal cross framesNo need for internal cross framesNo need for external cross framesNo need for external cross frames

Design is conservatively based on girders being Design is conservatively based on girders being supported at two ends, when casting deck. The supported at two ends, when casting deck. The actual production is based on girder sitting on actual production is based on girder sitting on prestress bed and supported continuously. prestress bed and supported continuously.

Open bottom allows easy inspectionOpen bottom allows easy inspection

Experimental workExperimental work

Concept has been Concept has been extensively tested extensively tested

7,500,000 Cycles 7,500,000 Cycles

Shear TestShear Test

Uxbridge Project – Boston MassUxbridge Project – Boston Mass

Opened to Traffic on Nov 2011Opened to Traffic on Nov 2011

Folded bending – KansasFolded bending – KansasGalvanizing – Valmont, KansasGalvanizing – Valmont, KansasCasting deck- Carrara- VermontCasting deck- Carrara- VermontContractor – John RocchioContractor – John RocchioDesign – Highway Bridge ServicesDesign – Highway Bridge ServicesIndependent design check- G.F.Independent design check- G.F.Owner – MassDOTOwner – MassDOTBridge instrumentation – University of MassBridge instrumentation – University of Mass

Four Folded plate with partial Four Folded plate with partial Depth deck delivered to siteDepth deck delivered to site

Edge girders will have the curbsEdge girders will have the curbscastcast

Anchor bolts are provided to boltAnchor bolts are provided to boltThe railing onsiteThe railing onsite

FabricationFabrication

Delivery of girders to precast Delivery of girders to precast Plan for casting sub-deckPlan for casting sub-deck

Girder DeliveryGirder Delivery

Deck FormsDeck Forms

Steel ReinforcementSteel Reinforcement

Casting DeckCasting Deck

Unit Ready for DeliveryUnit Ready for Delivery

Rigging for LiftRigging for Lift

Placing Girder UnitPlacing Girder Unit

Placing Girder UnitPlacing Girder Unit

Girder EndsGirder Ends

From BelowFrom Below

Finished StructureFinished Structure

Finished RoadwayFinished Roadway

Dr. Atorod AzizinaminiDr. Atorod Azizinamini402-770-6210402-770-6210

azizi@h-b-s.orgazizi@h-b-s.org