I-5 Lift Bridges Rehabilitation
Overview

Maintaining a “well-oiled” machine requires more than just oil. It requires proper balance, precision, and alignment of all moving parts. Such equipment is currently used to raise and lower the twin lift spans of Oregon’s I-5 bridges over the Columbia River. ODOT realized that the lift mechanisms started showing signs of growing misalignment and needed evaluation. 

Modjeski and Masters' (M&M) mechanical engineers started by conducting a detailed inspection of machinery components for both the Northbound and Southbound lift spans. Next, our bridge instrumentation and testing team strategically installed strain gages; an effective measure that M&M frequently employs to help trouble-shoot and test ailing bridges. Using the latest technical and rope access methods, our knowledgeable staff performed a detailed study without stopping traffic flow, an added value appreciated by both ODOT and the users of the busy I-5 Interstate Bridges. 

Bridge Geometry
Lift Span Length 275 feet
Lift Span Vertical Clearance 176 feet
Total Length 3538 feet
Longest truss span (fixed) 531 feet

On behalf of WJE, I would like to thank M&M for their hard work and professionalism in working with Brian and me during the instrumentation and inspection work. I believe the client was impressed by both the company’s knowledge and efforts.

- Jonathan McGormley, Project Manager, WJE