Veterans Memorial Bridge / Design-Build

Veterans Memorial Bridge / Design-Build


Fore River Parkway Abutment & Wall
MSE Precast Abutment
Location: 
Portland, Maine
Owner: 
Maine Dept. of Transportation
Contractor: 
Reed & Reed
Subcontractor: 
R.J. Grondin & Sons
Consultant: 
TY Lin International

As the gateway to Maine's largest metropolitan area, Veterans Memorial Bridge (VMB) carries the Veterans Memorial Parkway and more than 22,000 vehicles a day between Portland and South Portland.  In 2009 the Maine DOT issued a design-build RFP to replace the narrow and deteriorating original span and requiring a 100-year service life for the new structure.  The winning team comprised Reed & Reed (Woolwich, ME; general contractor), T.Y. Lin International (Falmouth, ME; bridge designer), GZA Geoenvironmental (Portland, ME; geotechnical engineer) and R. J. Grondin & Sons (Gorham, ME; earthwork/retaining walls contractor).  Their proposal won because it offered an extensive set of benefits:  it realigned and shortened the bridge, improved traffic flow through two intersections, provided for multiple modes of transportation, honored Maine's 150,000 veterans, and included significant public input to decisions regarding function and appearance.  The Reed & Reed team's monetary bid was $6 million below their competitors and their technical rating was equivalent to an additional $3 million, effectively providing a $9 million better value for Maine taxpayers.  Reinforced Earth® structures were an important part of the better value.

Realigning and shortening the bridge substantially reduced both construction and maintenance costs.  Grondin selected The Reinforced Earth Company (RECo) to design and supply the required walls and abutments, relying on RECo's extensive experience with complex projects to develop the connection to – and the extension of – the existing Reinforced Earth abutment where the VMB connects to the Fore River Parkway at the Portland end of the bridge.  RECo also designed and supplied the new abutment for the VMB itself, along with a connecting retaining wall and two other abutments.

RECo worked closely with the design-build team for two years from conceptual design (30% plans) in late 2009 to wall completion in December 2011.  Since wall designs were developed simultaneously with development of the contract drawings, quality assurance reviews, not only for the bridge but also for the walls and abutments, were critical to making sure everything would work correctly in the field.   This is an area where RECo excels: keeping in close communication with all team members at every step of the way.  The result, as stated by. Grondin's Project Manager, George Conley: "All in all, the walls went well, although it would have been easier if we didn't do the majority of the work in the winter.  Thanks for all your help with everything along the way.  Also thanks to your precaster [Dailey Precast, Shaftsbury, VT] for meeting our schedule and delivering excellent quality."

One key example of the design complexity was handling the excavation for the VMB's abutment.  When planning abutment installation, Grondin discovered that the required excavation for the reinforcing strips would impact the existing embankment supporting Fore River Parkway.  RECo's engineers were able to customize the design of the reinforcements to use shorter strips at the bottom.  This allowed for a flatter excavation backslope, maintaining the stability of the roadway above. 

Another excavation-related challenge arose from framing into and extending the existing Fore River Parkway bridge abutment. The active roadway, the existing abutment and piles, along with the many in-place reinforcing strips skewed around those piles, made for a complex problem when designing and constructing the extension of the existing abutment and the corner between the abutment and the wingwalls.  This time the solution was a shoring system supporting the in-place roadway and the backfill of the existing Reinforced Earth abutment, combined with new slip joint panels to stabilize and cover the joint between old and new portions of the Reinforced Earth structure.  The result is a neat, finished appearance and a perfect match with the existing abutment.

All the planning and coordination of the design-build process could not protect against the weather.  When unusually cold temperatures and freezing of the backfill threatened to delay construction of the VMB abutment, Grondin wanted to switch from a soil to a crushed stone backfill.  Once the new backfill was identified, RECo re-ran its design calculations based on the proposed material's lighter unit weight to be sure the as-designed and already-fabricated wall materials would work.  As often happens in such situations, the lower unit weight was offset by the crushed stone's higher shear strength, resulting in greater pullout resistance along the reinforcing strips.  After validating the design using the new backfill, RECo annotated the plans to show where the stone was to be placed and construction of the Veterans Memorial Bridge abutment was completed without delay.

Portland's new Veterans Memorial Bridge opened to traffic with a gala celebration on June 28, 2012.  The dedicated bike and pedestrian path is a major attraction, as are the scenic outlooks accented by curved poles that appear to wave gracefully like the windswept grasses in the nearby marshes.  And while everyone appreciates the improved traffic flow and long life expectancy, few who enjoy this signature structure realize the significant role played by the Reinforced Earth structures, and by the RECo team, in the structural and aesthetic success of this project.