1. SHRP 2 - FIRST DEMO PROJECT KEG CREEK, IOWA R04 – “BRIDGE DESIGNS FOR RAPID RENEWAL” Sandra Larson, P.E. Iowa Department of Transportation Research and Technology Bureau Director Sandra.larson@dot.iowa.gov RAC/TRB 2012 Annual Meeting Burlington, VT

2. THREE MESSAGES SHRP 2 Overall Plan - Leading to Implementation of Products Accelerated Bridge Construction (ABC) Background Iowa’s SHRP 2 Demo Project Details– Keg Creek Thanks to Neil Pedersen (SHRP 2) and Ahmad Abu- Hawash (Iowa DOT) for slide information 2

3. SHRP 2 (Second Strategic Highway Research Program) Overall Plan - Leading to Implementation of Products

4. SHRP 2 PLAN Research (2005 - 2013) 100+ research projects 100+ research projects Administered by TRB Administered by TRB Development (Now through 2015) Pilots and demonstrations Pilots and demonstrations Testing and refinement of products emerging from research Testing and refinement of products emerging from research Implementation (2012 - forward) Partner agencies prioritize products for implementation Partner agencies prioritize products for implementation Selected products systematically integrated into current transportation practices Selected products systematically integrated into current transportation practices 4

5. Keg Creek - SHRP 2 Demo Project SHRP2 funds: –$250,000 for construction –Assistance with design of bridge through consultant –Assistance with project details and problem solving –Held showcase, produced video HFL funds: $600,000 or 20% of construction cost Iowa DOT research and construction funds, staff time, commitment of resources Iowa State University research testing 5

6. 6 Safety: fostering safer driving through analysis of driver, roadway and vehicle factors in crashes, near crashes, and ordinary driving Renewal: maintaining and repairing the deteriorating infrastructure using already-available resources Reliability: managing non-recurring events to create more predictable travel times Capacity: building a highway system that creates minimum disruption and meets the environmental, and economic needs of the community. SHRP 2 Focus Areas

7. SHRP 2 - Definition of Success 7 5-6 States adopt as standard practice Additional states follow the lead AASHTO and FHWA provide continuing support Private sector buy-inPositive impact on practiceCost-effective use of products

8. Accelerated Bridge Construction (ABC) in Iowa

9. Iowa DOT ABC Deployment Strategy – past several years Develop skills and design details through demonstration projects (IBRD, HfL, SHRP2,..) Invest in research and include laboratory and field testing to confirm constructability and performance. Participate in national pooled fund studies Involve local construction industry and hold ABC workshops. Develop policies for ABC 9

10. ABC/PBES Prefabricated Bridge Elements and Systems (PBES): it is a strategy to accelerate bridge construction that employs prefabricated individual Elements such as beam, deck, abutment footing, pier column, pier cap, etc. Or entire superstructure System that is assembled off-site and moved into place.

11. Why use ABC? –To deal with schedule constraints Limited time-window due to special events Emergency replacement due to natural disasters, accidents, or intentional acts –To minimize impact on local traffic Access to business Commuters Essential services –To deal with the unavailability of suitable detour

12. ABC: Benefits Reduced public inconvenience Improved public perception Improved road users and workers safety Reduce negative economic impact on local businesses Perhaps improve the durability of the structure

13. ABC: Disadvantages Substantial increase in construction cost: fewer bridge replacements Contractors are generally uncomfortable with the PBES concept: higher cost Requires the development of new design standards and specifications: higher design cost

14. Case Study: Keg Creek Lessons Learned SHRP 2 Program First Demo Project

15. Keg Creek Bridge - IT’S A BIG DEAL - Iowa DOT wins America’s Transportation Award, announced July 18 2012: The Iowa DOT received an award in the “Best Use of Innovation” category for the U.S. 6 bridge over Keg Creek in Pottawattamie County. U.S. 6 bridge over Keg Creek in Pottawattamie CountyU.S. 6 bridge over Keg Creek in Pottawattamie County This bridge was completely prefabricated off-site and then assembled at the construction site using an accelerated bridge construction method. Utilizing this approach, the road was closed for only two weeks. 15

16. Background SHRP2 – R04 Research Team needed to demonstrate ABC design concept for typical multi-span stream crossings – a common rural bridge replacement Proposed a demonstration project in Iowa Successful project may pave the way for developing national ABC standards A bridge on US 6 over Keg Creek in Pottawattamie County met the objectives

17. EXISTING BRIDGE 180’ x 28’-0 Continuous concrete girder bridge Built in 1953 3 spans 53’6”,73’,53’6” Moderate sized, typical rural crossing Small, meandering stream Narrow bridge width on primary road system Sufficiency rating 33

18. Keg Creek - Project Data Design: HNTB Testing: ISU Bridge Construction Cost: $2,658,823 Unit cost: $231 per sq.ft. ($124 estimated for conventional in Iowa) Incentive/Disincentive : $22,000 per day SHRP2 funds: $250,000 HFL funds: $600,000 or 20% of cost New bridge: 204’-6 x 44’-0 Prefabricated Steel Modular Superstructure on Precast Substructure supported on Drilled Shafts.

19. Why Keg Creek? Typical rural, moderate size stream crossing in Iowa. Indicative of many bridges throughout the mid-west and country. SHRP2 looking to standardize ABC design plans. Detour: 22 mile detour less desirable for traveling public over 4 to 6 month period versus 2 week ABC period. Detour: 22 mile detour less desirable for traveling public over 4 to 6 month period versus 2 week ABC period. Schedule: already programmed for 2011 construction. Schedule: already programmed for 2011 construction.

20. Iowa Bridge Farm (Phase 1)

21. Precast Substructure Components Casting (Phase 1)

22. Superstructure Modules – Structural Steel Assembly (Phase 1)

23. Superstructure Modules – Deck Forming (Phase 1)

24. Deck Concrete Placement (Phase 1)

25. Drilled Shaft Construction (Phase 1)

26. Abutment / Wing Erection 93 kips 26 kips

27. Column Assembly 52 kips

28. Bedding and Coupler Grouting

29. Cap Beam Assembly 168 kips

30. Superstructure Module Transport 102-112 kips 69-80 kips

31. Module Assembly

33. Final Module Placement

34. Flooded Backfill System

35. Precast Approach Preparation 35 kips

36. Precast Approach Slab Placement 31-37 kips

37. UHPC Placement

38. Completed Bridge

39. Conclusions R04 - ABC design concept was successfully demonstrated, but there were some challenges along the way. Post construction review identified problem areas, as expected, and provided recommendations for improvements which will be documented in the final report. As the result of this project (and other past ABC projects), Iowa DOT gained a better understanding of risks and benefits associated with ABC and is developing ABC policy and planning more ABC bridges.

40. Project Website http://www.iowadot.gov/us6KegCreek/ Questions? Thanks to: Neil Pedersen, SHRP 2 Ahmad Abu-Hawash, Iowa DOT For slide material