ASPIRE is a quarterly magazine published by PCI in cooperation with the associations of the National Concrete Bridge Council. The editorial content focuses on the latest technology and key issues in the Concrete Bridge Industry.
Issue link: http://www.aspiremagazinebyengineers.com/i/297030
In late 2009, construction of new t w i n a rc h b r i d g e s c o m m e n c e d i n E u g e n e , O r e . T h e b r i d g e s c a r r y Interstate 5 (I-5) southbound (SB) and northbound (NB) over the Willamette R i v e r, a l o c a l h i g h w a y, r a i l r o a d tracks, an off-ramp, and two multi- use paths. To span the complex project area, the bridge lengths are 1759 and 1984.7 ft for SB and NB, respectively. T h e b r i d g e s r e p l a c e t h e o r i g i n a l structure built in the early 1960s, which was closed in 2004 due to structural deficiencies. Since 2004, t r a f f i c h a d b e e n u s i n g a d e t o u r bridge near the alignment of the NB replacement structure. The Willamette River Bridges (WRBs) are exceptional in many respects: • The spans over the river are the longest concrete arch spans in Oregon. • The project is the last and largest of the $1.3 billion, multi-year Oregon Transportation Investment Act (OTIA III) program. • It is the largest bridge replacement p r o j e c t e v e r u n d e r t a k e n b y t h e O r e g o n D e p a r t m e n t o f Transportation (ODOT). Structural Arrangement Oregon has an impressive inventory of historic concrete arch bridges, providing aesthetic and functional crossings of estuaries and rivers throughout the state. More than 20 of the structures completed in the 1920s and 1930s are credited to Conde McCullough, a highly influential engineer who worked for ODOT into the 1940s. The WRBs fit nicely with these older bridges that are well known for their aesthetic mix of Romanesque, Gothic, and art-deco architectural styles. However, the WRBs also represent two of the few contemporary concrete arch bridges in Oregon. The basic form of the WRBs builds on the Maple Avenue Bridge, a 2005 award winning OBEC profile I-5 WILLAMETTE RIVER BRIDGES / EUGENE, OREGON BRIDGE DESIGn EnGInEER: OBEC Consulting Engineers, Eugene, Ore. ConSTRuCTIon EnGInEER: Jiri Strasky, Consulting Engineer, Greenbrae, Calif. PRIME ConTRACToR: Hamilton Construction Company, Springfield, Ore. ConCRETE SuPPlIER: Knife River, Harrisburg, Ore. by Jim Bollman, OBEC Consulting Engineers I-5 Willamette River Bridges Completed southbound bridge, with northbound work bridge in the background. All photos: OBEC Consulting Engineers. Longest concrete arch spans in Oregon 36 | ASPIRE , Summer 2012 P R O J E C T ASPIREBook_Sum12_R02.indb 36 6/29/12 12:39 PM