All states have bridges that could use, if not a little TLC, full replacement. Once you've got the funding, the next challenge is disrupting driver commutes as little as possible.
The Rhode Island DOT (RIDOT) accomplished both on a two-bridge, $16.7-million replacement project with a $663,000 budget contingency.
Built in 1959, the East Shore Expressway Bridge 475 in East Providence carries 17,000 vehicles per day. it's been classified as structurally deficient for more than 20 years.
Between Sept. 9 and 13, 2016, the agency demolished and replaced the old bridge with a single-span structure. The process took 80 hours thanks to accelerated construction methods.
Manafort Construction, the general contractor, used precast concrete approach slabs, abutment caps, wing wall sections, parapets, and end posts with separate precast footings connected by grouted splice sleeves to assemble new decks on large supports in temporary staging areas next to the old bridge. Detailed, manufactured, and delivered by Oldcastle Precast-Rehoboth, Mass., the components were match-cast and/or test-fitted before installation to ensure a perfect fit and avoid any delays during final erection.
Accordingly, the substructure units were constructed behind the existing interior piers, resulting in a span length of approximately 122 feet. This allowed traffic to remain uninterrupted with the exception of minor closures for erection purposes.
This approach to construction enabled the agency to open the new bridge one year earlier than would be possible using conventional construction methods. In addition, if the agency hadn't used this method, the traveling public would have been impacted over the course of a year with each ramp only opened at half capacity.
The rest of the project is on budget and on schedule and will reach final completion in June 2017.
Encouraged by that success, RIDOT began replacing the McCormick Quarry Bridge on Sept. 23, 2016.
"The lessons we learned through the first 80-hour process certainly aided us during the replacement of the second bridge,” says RIDOT Director Peter Alviti Jr. "This construction approach lets us complete the job of replacing these deficient and obsolete structures as quickly as possible with as little impact as possible to the traveling public."