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/306894
24 | ASPIRE , Winter 2007 Milwaukee County officials knew they faced a number of key challenges when they decided to replace the existing B r a d y S t r e e t p e d e s t r i a n p a t h w a y along the lakefront. To accomplish the range of goals on a difficult site while providing strong aesthetic appeal, the designers created a unique post- tensioned, three-span concrete bridge that will have minimum maintenance needs throughout its lifetime. The original structure provided access to neighborhoods on top of a bluff along a bike trail and continued to a nearby park on Lake Michigan. It included a series of stairways to accommodate steep slopes coming down from the bluff and a reinforced concrete bridge that led pedestrian traffic via another stairway to the lakefront. Aesthetics for the new bridge were of paramount concern, as the neighborhood has a high profile, hosting the Milwaukee Art Museum and the Milwaukee County War Memorial as well as a number of architecturally interesting bridges. Vertical Slope— A Key Challenge "The project's main goal was to address the steep vertical slope across the pathway and make it accessible to pedestrians and bicycles, and comply with the Americans with Disabilities Act (ADA)." explains Yan Nenaydykh, vice president of Bloom Consultants LLC in Milwaukee. He and his colleagues Darrell Berry, project manager; Boris Sloutsky, senior structural engineer; and Yakov Braverman and Anil Kurian, project engineers worked with Edwards & Kelcey (E&K), to create a plan to meet the various site requirements. E&K developed the overall bike trail project, while Bloom Consultants designed and engineered the bridge itself. A key challenge was to improve the vertical alignment, which E&K proposed accomplishing with a single switchback to address the steep slope. The design offered a constant 5% vertical slope from end to end. The existing stairway at the eastern end, connecting to the lakefront, was replaced with a circular r a m p t h a t m e t A D A a n d A A S H TO requirements. The goal then became finding an approach and materials that AwA rdS Award of Excellence, 2006 PCA Tenth Biennial Bridge Awards Competition profile B r A dY STr EET Bridg E / CITY OF MILWAUKEE ProjECT ConSulTAnT Edwards & Kelcey, Morristown, New Jersey Bridg E EnginEEr And ArChiTECT Bloom Consultants LLC, Milwaukee, Wisc. PrimE ConTrACTor Lunda Construction Co., Black River Falls, Wisc. ConCrETE SuPPliEr Zignego Ready Mix, Waukesha, Wisc. PoST-TEnSioning ConTrACTor Dywidag-Systems International USA Inc., Bolingbrook, Ill. Post-Tensioned Design Creates Pedestrian Landmark by Craig A. Shutt Concrete meets a variety of functional challenges while providing strong eye appeal for pedestrian bridge in highly visible neighborhood By creating a 125-ft-long center span for the bridge, designers eliminated the need for a center column, saving construction time and material cost while producing a sleeker appearance. ASPIRE_win07.indb 24 12/29/06 2:11:58 PM