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/335723
PROJECT Kahoma Uka Bridge. By David Fujiwara and Eric Matsumoto, KSF Inc. PROFILE KAHOMA UKA BRIDGE / LAHAINA, MAUI, HAWAII BRIDGE DESIGN ENGINEER: KSF Inc., Honolulu, Hawaii PRIME CONTRACTOR: Hawaiian Dredging Construction Company Inc., Honolulu,Hawaii POST-TENSIONING CONTRACTOR: Schwager Davis Inc., San Jose, Calif. OTHER MATERIAL SUPPLIERS: Reinforcement, Associated Steel Workers Ltd., Kapolei, Hawaii; Friction pendulum bearings, Earthquake Protection Systems Inc., Vallejo, Calif. In order to improve the quality of life for the western Maui community, the Hawaii Department of Transportation (HDOT) assessed the input from the public and made the dream of a Lahaina Bypass into a reality. The bypass provides an alternative route to Honoapiilani Highway in the vicinity of Lahaina town, which alleviates traffic congestion and improves circulation of vehicles in the area. This new roadway also contains a truly unique structure to traverse Kahoma stream. The final design of Kahoma Uka Bridge was selected after considering a myriad of structural types and construction methods. The evaluation process included the desired span length, existing conditions, environmental impacts, material strengths and capabilities, aesthetics, and cost. As a result, the community was presented with a horizontally curved, 60-ft-wide, 360-ft-long, single-span, low-profile, inverted tied arch bridge that neither obstructs the scenic view nor interferes with the stream environment below. Request for Proposals In 2006, the contractor was awarded the design-build contract to complete phase 1A of Lahaina Bypass. Based on the request for proposal requirements, the design team developed a straight, 350-ft-long, single-span, inverted tied arch bridge with a constant cross slope of 2%. A Cultural Discovery Work on the project was halted in May 2007 when 30 acres of historical agricultural terraces were discovered in the path of the new roadway. To respect this culturally significant site, native Hawaiian groups and lineal descendants were consulted. With their input, a plan was developed to re-align the roadway toward the ocean and away from the terraces. The bridge, which was previously straight, now required a horizontal curve with a radius of 1200 ft and superelevation. This new configuration significantly magnified the complexity of the structure. With the full cooperation and dedication of everyone involved, the redesign of Kahoma Uka Bridge expeditiously proceeded in September 2009. (continued next page)