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/439391
PROJECT Citrus Ave. and Cherry Ave. Overcrossings by Brett Makley and Noel Shamble, T.Y. Lin International Architectural ingenuity and structural resilience came together to create two landmark overcrossings for the city of Fontana, Calif. The two bridges incorporate characteristics of the local community, serve as gateways to the city, and are able to withstand the effects of an earthquake in the seismically active region of southern California. The Citrus Avenue Overcrossing and the Cherry Avenue Overcrossing, located just 2 miles apart along Interstate 10 (I-10) in the county of San Bernardino, are two important components of two full-interchange reconstructions. Improvements to the interchanges were needed to alleviate congestion and ease the heavy truck traffic that travels from the Los Angeles area ports easterly through California to other states. The San Bernardino Associated Governments (SANBAG), in cooperation with the city of Fontana, the county of San Bernardino, and the California Department of Transportation (Caltrans), led the effort to reconstruct the interchanges. The project included • replacing the existing overcrossings with wider and longer cast-in-place prestressed concrete box girder structures, • widening the existing precastprestressed concrete I-girder overcrossing structures over Union Pacific Railroad’s tracks, and • widening and improving the on-and off-ramps to I-10. The I-10/Citrus Avenue Interchange was completed in the spring of 2014. It will soon be followed by improvements to the I-10/Cherry Avenue Interchange, which is expected to be completed by early 2015. The overall project—which must be completed on-time to meet strict, accelerated funding deadlines— includes four bridges, new loop ramps, numerous retaining walls, and a major drainage channel. Construction The operational capacities of the original interchanges, both of which were constructed to rural standards in the 1950s, were severely challenged by the large volume of traffic created by subsequent development in the city of Fontana. To minimize traffic impacts in the area and maintain existing traffic flow, a two-stage construction technique was implemented. First, half of the new bridge was constructed parallel to the existing structure. For the overcrossings, the existing structure was then demolished and replaced. For the overheads, the existing structure was overlaid with a combination of polyester concrete and structural concrete to match the deck grades of the widening. For both structures, the two halves were connected with closure placements to create one continuous structure at each location. Aesthetic Starting Point— Cherry Avenue Overcrossing The starting point for the architectural design of the Cherry Avenue and Citrus Avenue Overcrossings was site context. The first structure to be developed was the Cherry Avenue Overcrossing. The stakeholders wanted an eye-catching design that would reflect the city of Fontana’s growing community, while providing a special gateway for the nearby Auto Club Speedway racetrack. Because Cherry Avenue is the racetrack-entrance road, stakeholders wanted the structure to be a visual landmark for everyday I-10 travelers, avid race fans, and even NASCAR national TV coverage. PROFILE: CITRUS AVENUE AND CHERRY AVENUE OVERCROSSINGS / FONTANA, CALIFORNIA BRIDGE DESIGN ENGINEER AND ARCHITECT: T.Y. Lin International, San Diego, Calif. PRIME CONTRACTORS: Cherry Avenue Interchange: Ortiz Enterprises Inc., Irvine, Calif.; Citrus Avenue Interchange: Brutoco Engineering & Construction, Fontana, Calif. PRECASTERS: Cherry Avenue Overcrossing: Coreslab Structures Inc., Perris, Calif.—a PCI-certified producer; Citrus Avenue Overcrossing: Oldcastle, Perris, Calif.—a PCI-certified producer POST-TENSIONING CONTRACTOR: Dywidag Systems International USA Inc., Long Beach, Calif.