Bridge Design & Structural Engineering
Sakonnet River Bridge
Portsmouth/Tiverton, RI
Key Design Element: Bridge Rehabilitation and Replacement
Client: Rhode Island Department of Transportation
Two Capitol Hill, Providence, RI
Construction Cost: $163+ Million
Construction Completion: 2014
Benefits:
- Improved public safety and seismic protection
- Increased transportation capacity
- Added bicycle and pedestrian path
Project Description:
The prior, ca. 1950 Sakonnet River Bridge carried Route 24 over the Sakonnet River in Tiverton and Portsmouth, RI. The bridge spanned approximately 3,000 feet and carried in an average of 40,000 vehicles per day. Commonwealth Engineers & Consultants, Inc. was retained to conduct an extensive investigation, testing and comprehensive field review to determine the extent and type of repair work required.
Based on the complete inspection and testing program, a report was prepared outlining the proposed rehabilitation work and an associated cost estimate. Based on the high initial cost estimate, an independent value-engineering study was undertaken, which also investigated the cost effectiveness of constructing a new bridge.
The project went through an Environmental Impact Statement (EIS) process which considered the environmental and socioeconomic impacts of various alternatives, including rehabilitation and structure replacement. The final recommendation of the EIS was to replace the bridge on a new alignment just to the south of the existing bridge.
CE&C managed the preliminary and final design phases of the bridge replacement, the team for which included over twenty local and national sub-consultants. CE&C also prepared a design for the “steel bid alternative” structure, including roadway approach design, traffic management/phasing, and permitting. The bridge was opened to traffic in 2012. CE&C provided construction services to RIDOT throughout, including Environmental Compliance Monitoring as required by the permitting agencies. It is a tribute to the entire design and construction team that the construction change orders have been limited to about 0.34% of the construction bid value.
Additionally, CE&C has performed or is performing the following tasks:
Prepared a maintenance manual for the bridge to address such unique characteristics as pile anode and weathering-steel girder corrosion monitoring.
Prepared an FEIS ReEvaluation for the implementation of tolls.
Prepared an FEIS ReEvaluation to address various demolition techniques for the former bridge, including controlled demolition.
Prepared the initial Operation and Maintenance Cost Plan for the former RITBA Director of Engineering.
As further demonstration of its success, it is notable that this project is the recipient of the following awards:
National Steel Bridge Alliance - "Merit Award, Major Span Category" – 2014
Deep Foundations Institute - "Special Recognition Award" - 2014
Construction of the bridge was completed in 2014.
Pawtucket River Bridge
Pawtucket, RI
Key Design Element: Major Bridge Replacement
Client: Rhode Island Department of Transportation
Construction Cost: $140 Million
Construction Completion: 2013
Project Description:
The prior Pawtucket Bridge No. 550 was a five-span, two-girder, pin and hanger (suspended cantilever) steel bridge carrying Interstate Route I-95 over city streets as well as the Seekonk River in Pawtucket, Rhode Island. With an overall length of 702’, the superstructure consisted of three “layers” of primary framing components: main girders, transverse floor beams, and longitudinal stringers. This framing system rendered the structure non-redundant and fracture critical. Commonwealth Engineers & Consultants, Inc. (CE&C) conducted an extensive investigation and field inspection of the bridge. Excessive deterioration was found at the cantilevered sections of the floor beams, top flanges of the interior floor beams, and top and bottom flanges of the longitudinal girders and stringers. This information was used to perform a load rating and capacity analysis for the as-built condition. The structural evaluation also included a fatigue analysis and assessment.
Due to the high cost of rehabilitation and the low live load capacity rating, various bridge replacement scenarios were assessed. As a result of partnering with State, City, and private citizens’ groups, a steel open-spandrel deck arch structure was selected for the replacement bridge, with selective use of simple, geometric design elements to suit the architectural style of buildings in the region. CE&C prepared A+B contract bid documents for this 300-foot open spandrel steel deck-arch structure, an architectural form proposed and refined by CE&C. Also, five other nearby bridges were either replaced or rehabilitated as part of this project. The 180,000 daily vehicles on I-95 were maintained successfully by detour routes and traffic phasing, both of which were studied extensively during design. Extensive construction phasing was required to maintain all travel lanes of both northbound and southbound of Route 95, which was widened to accommodate traffic during construction as well as a new collector-distributor road for the traffic interchange at the bridge site.
The new structure comprises multiple metalized tubular steel arches supporting ABC (accelerated bridge construction) full-depth precast post-tensioned deck panels. Numerous cast-in-place and mechanically stabilized earth retaining walls were included in the project. The bridge also includes architectural pylons, aluminum sculptures and accent lighting. High-efficiency lighting is used extensively for both highway and accent illumination.
Construction was completed in 2013.
East Shore Expressway Bridge 475 & McCormick Quarry Bridge 476
East Providence, RI
Key Design Element: Bridge Replacement by Self-Propelled Modular Transport
Client: Rhode Island Department of Transportation
Two Capitol Hill, Providence, RI
Construction Cost: $12.7 Million
Construction Completion: 2017
These two bridges carry northbound (Br 476) and southbound (Br 475) East Shore Expressway traffic over US Route 6 in East Providence, RI.
The existing East Shore Expressway Bridge No. 475 was a three-span continuous, reinforced concrete haunched-girder superstructure with concrete substructures. McCormick Quarry Bridge No. 476 was a three simple-span-concrete I-Girder superstructure with concrete substructures. They were replaced with single-span steel plate-girder superstructures, composite with the concrete decks, supported on Geosynthetic Reinforced Soil (GRS) abutments. As an Accelerated Bridge Construction (ABC) Project, the new bridge superstructures were built off-line and moved into final location via Self-Propelled Modular Transporters (SPMTs). Other ABC features included the use of precast elements for all substructure components.
CE&C was responsible for the complete design of both structures, including preliminary studies, geotechnical and structural analysis and design, and final contract document preparation. In June of 2018, CE&C collaborated with RIDOT on an international webinar showcasing this project for the Florida International University ABC/UTC Series. A pdf of this presentation can be downloaded at:
Natick Bridge
West Warwick, RI
Key Design Element: Bridge Replacement
Client: Rhode Island Department of Transportation
Construction Cost: $7.1 Million
Construction Completion: 2015
The Natick Bridge carries East Avenue over the Pawtuxet River between Warwick and West Warwick, RI. Part of the Comprehensive Bridge Improvement Program, the advanced deterioration of this bridge necessitated its replacement to maintain a vital link between its two neighboring communities.
The existing bridge was a 210-foot long, three-span structure that was eligible for listing in the National Register of Historical Places. A Structure Evaluation Report determined that the bridge needed to be replaced in its entirety and a Type Study was performed to evaluate potential replacement alternatives. A two-span prestressed concrete beam structure placed on drilled shafts, with pre-cast architectural fascia panels to replicate the existing bridge’s arch appearance, was selected.
Commonwealth Engineers & Consultants, Inc. prepared contract documents for the replacement. The work included placing the bridge on a new roadway alignment to improve the substandard alignment of the approach roadway geometry, to improve safety for pedestrians and bicyclists and to minimize environmental impacts during and after construction. Cultural and environmental studies were performed to address flooding concerns of the surrounding area and to document the historic significance of the bridge. CE&C also performed an emergency inspection of the existing bridge following historic flooding in 2010 and developed repair details to restore the bridge to service until the new bridge could be opened to traffic. The construction was completed in 2014.
Division Street Bridge
Pawtucket, RI
Key Design Element: Bridge Rehabilitation
Client: Rhode Island Department of Transportation
Construction Cost: $5.5 Million
Construction Completion: 2018
This project comprised the repair of a ~140-year-old continuous stone and brick arch bridge in Pawtucket, RI. The unique makeup of this bridge presented challenges regarding repair techniques. First, erosion of underlying river deposits required repairs, for which grout-bags were employed. This system utilizes underwater grout-injected sacks to confine the grouted erosion mitigation system. Secondly, the multiple-wythe brickwork of the arches required a sophisticated framework system to support the historically “correct” repairs. As with several of our projects, the composition of the special provisions was critical to ensure minimal issues during construction.
Other work included the removal, restoration, and reinstallation of ornamental sidewalk brackets, and the installation of a new timber plank sidewalk deck.
