THE CONCRETE BRIDGE MAGAZINE

WINTER 2018

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/922349

Contents of this Issue

Navigation

Page 9 of 59

8 | ASPIRE Winter 2018 2013. Serving as the lead designer, RS&H, working with Archer Western Contractors (Walsh Group), designed the 3100-ft-long structure as a 19-span concrete-beam bridge using Florida I-beams and hammerhead-type piers and drop-in spliced girders. Two 250-ft spans allowed the bridge to cross the St. Lucie Waterway with fewer piers, helping to address the highly sensitive environmental concerns. "This project was a great success for our design-build practice, which has become a large part of our firm's g ro w t h s t r a t e g y, " s a y s B a r r y. " I t reinforced our value and relationships with major contractors and expanded our transportation-client base beyond state and local agencies." The bridge won numerous awards, including a National Award of Excellence from the Design-Build Institute of America. Environmental Concerns Terrain issues often lead to creative concepts. On the 460 Connector project in Breaks, Va., RS&H performed CEI oversight of the twin 1733-ft-long cast- in-place concrete segmental box-girder structures erected by the balanced- cantilever method. The tallest bridges in Virginia, they were built from the top down because of the mountainous site. "Cast-in-place segmental concrete superstructure construction made the most sense," says Barry. "Access from the ground was difficult, and large girders could not be delivered to the remote construction site. Environmental and site access issues have become a driving force for using segmental concrete and for concrete in general." The 460 Connector also was significant for RS&H because it represented the firm's first CEI oversight project outside of its home state. "We were chosen, in part, because of the expertise we gained from our segmental experience in Florida," Barry says. T h e f i r m 's w o r k w e n t b e y o n d construction oversight, however. "We also were tasked with developing new segmental specifications for the project and for VDOT [Virginia Department of Transportation] as a whole. The project was a significant growth opportunity for us as a firm and grew our segmental reputation as well." Embracing Innovation The 460 Connector project led to further expansion in Virginia, including CEI oversight for the Lesner Bridge replacement project. This ongoing project features twin 1575-ft-long precast concrete segmental box-girder bridges for a new client, the City of Virginia Beach. "A concrete segmental design was chosen due to difficult conditions on the site and for aesthetic reasons. This is a significant structure for the city, and both aesthetics and long-term durability were very important to them," Barry says. For RS&H, the project "was significant because it continued our segmental experience on a broader scale and added a new client outside of Florida." A key element of the project's design was the goal of achieving a 100-year lifespan. The designer, FIGG Engineering Group, addressed that goal by specifying high-performance 8-ksi concrete. "It was an unusual product to specify as a production-level concrete," says Barry. Because of the highly aggressive environment adjacent to the Chesapeake Bay, the concrete had to achieve a low The 460 Connector in Breaks, Va., features twin cast-in-place concrete segmental structures that are the tallest in the state. RS&H also assisted the Virginia Department of Transportation with the development of segmental bridge specifications for this and future projects. 'Success depends a lot on how open the owner is to change.' The North Interchange Project in Jacksonville, Fla., features a precast concrete segmental box-girder overpass. The concrete segmental design resolved challenges in design and construction created by difficulties with placing the overpass over existing roadways and limited right-of-way. It was the first project to specify duct couplers for joining internal post-tensioning ducts, which is now a standard technique.

Articles in this issue

Archives of this issue

view archives of THE CONCRETE BRIDGE MAGAZINE - WINTER 2018