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/319569
44 | ASPIRE , Fall 2010 S TAT E S TAT E T he Utah Department of Transportation (UDOT) has experienced great success with Accelerated Bridge Construction (ABC) methods in the past 4 years. ABC, which applies traditional design principles in an innovative way, promises a faster approach to building concrete bridges. UDOT's intent is to reduce project duration and save time and money for road users and other stakeholders such as utility companies and railroads. The transportation community in the United States is familiar with UDOT's recent bridge moving projects–19 bridges have been built off site then moved into place using various new technologies. However, projects using other ABC methods have not received as much national attention. UDOT's less familiar projects have served as the impetus to develop new standards and specifications for structural elements. "This is new technology," says Fred Doehring, deputy structures engineer at UDOT. "We're doing a lot of research and development not only for Utah but for the rest of the country right now." UDOT seeks to design and build quickly as soon as project funding is secured. And because concrete is made of readily available materials, components are quick to produce. A bridge deck on I-70 and three bridges on U.S. 6 provide good case studies about how UDOT has partnered with the private sector to pioneer ABC methods that deliver high-quality concrete bridges much faster than traditional means. i-70 Bridge over Eagle Canyon A concrete bridge deck replacement project in a remote Utah location proved to be an ideal application for an ABC approach. The Eagle Canyon Arch Bridge, originally built in 1966, is located on I-70 at Mile Post 118 between Salina and Green River in southern Utah, over 200 miles from Salt Lake City. The bridge crosses a 480-ft-wide canyon and is 289 ft high. The bridge deck replacement was designed by Horrocks Engineers of Pleasant Grove, Utah, and constructed by Granite Construction Company of Salt Lake City. UDOT used a construction m a n a g e r / g e n e r a l c o n t r a c t o r ( C M G C ) contracting appr oach that brings design engineers and construction contractors on board throughout the process. According to Larr y Reash with Horrocks Engineers, the CMGC process intent is to "form a partnership between UDOT, the owner, the designer working for UDOT, and the contractor. This partnership is developed during the design phase to minimize risk, develop a project schedule, identify potential innovations, and develop a project cost model." During design, the Granite and Horrocks team worked together to analyze construction loading on the bridge. The investigation showed that removing the entire deck at once would potentially lead to instability of the arches so the deck panels would need to be removed and replaced section by section. The r emote location and pr oximity to sensitive cultural and scenic resources made AccelerAted Bridge construction: Tradition meets innovation at the Utah Department of Transportation by Catherine Higgins, Utah Department of Transportation During redecking of this arch bridge over Eagle Canyon, sections of the old deck were removed and replaced with groups of five new full-width precast concrete panels until reaching midspan. The work then moved to the opposite end. Photo: Granite Construction Company. Deck panels being installed on the I-70 Bridge over Eagle Canyon. Photo: Granite Construction Company. ASP10-1704.indb 44 9/17/10 2:06 PM