Approaches to Historic Bridge Rehabilitation Case Study #3 Yaquina River (Eddyville) Bridge (Pony Truss) by Ray Bottenberg, Oregon Department of Transportation

Yaquina River (Eddyville) Bridge Case study #3 Yaquina River (Eddyville) Bridge Location Milepoint 23.38 on US 20 in Eddyville, Oregon Description of Setting Town of <1000 in rural, forested area Description of Bridge Date Original construction 1923 Widened 1962 Length 132 Feet Span Type (s) 80 foot steel pony truss Precast reinforced concrete channels in approaches

Yaquina River (Eddyville) Bridge Case study #3 Yaquina River (Eddyville) Bridge Date and Cost of Rehab 2006 $424,000 Designer ODOT – Ray Bottenberg Client/Owner ODOT Contractor S&K Painting

Case study #3 Load Rating Issue Bridge and old alignment of US 20 to be given to Lincoln County. County wanted load rating before accepting bridge and roadway.

How Load Rating Issue Was Resolved Case study #3 How Load Rating Issue Was Resolved Field visit with rebar locator to recreate As-Built data Field visit with Portable Hardness Tester to verify material strength ~14% increase in strength over design values Strain gage survey Left: Strain Gage Monitoring Right: Typical Strain Gage Installation

How Load Rating Issue Was Resolved Case study #3 Removal of 4-6” Asphalt concrete wearing surface and replacement with 2” wearing surface This eliminated enough dead load to solve the load rating issue

Case study #3 Corrosion Issues Bridge and old alignment of US 20 to be given to Lincoln County. County wanted corrosion damage addressed. Sufficiency rating of 26.8 partially a result of corrosion damage and paint condition. Coating was approximately 40 years old. Left: Lower chord tie plate corrosion Right: Corrosion of floor beam connection above bearing

Left: Lower chord tie plate corrosion damage Case study #3 Left: Lower chord tie plate corrosion damage Right: Section loss in lower chord connection plate

How Corrosion Issue Was Resolved Case study #3 How Corrosion Issue Was Resolved 40-year-old Lead-Based Coating System replaced with 3-coat cured urethane system after abrasive blasting. corroded tie plates and lacing bars were replaced in-kind. Lower chord connections and end floor beam connections received extra intermediate coat of urethane-tar.

How was Section 106 handled Case study #3 How was Section 106 handled Bridge was determined “Potentially Eligible” under Section 106. Project cleaned and recoated the bridge and repaired minor corrosion issues. Repair details were designed as “In-Kind” replacement of corroded components. Repair details were reviewed and concurred by State Historic Preservation Office. Original bridge color (black) determined from 1923 files, project specified black color. “No Adverse Effect.”

How was Section 4(f) handled Case study #3 How was Section 4(f) handled Section 4(f) was largely a non-issue for this project. The historic bridge was not demolished. “No Adverse Effect” on historic quality.

Lessons Learned/Conclusions Case study #3 Lessons Learned/Conclusions Hardness testing and strain gage testing are reasonable steps to refine load rating, when bridge shows no signs of overload distress. Remove excess ACWS. Minor rehabilitation work and change in use can significantly improve sufficiency rating.