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09/25/2009
First NEXT Beam Project Awarded
York, ME - The first Northeast Extreme Tee Beam (NEXT) has been awarded in Maine. The project in York ME is a seven span structure over the York River. It will involve the fabrication of 28 NEXT beams varying in length from 55' to 80'. The NEXT beam was developed by the PCI Northeast Bridge Technical Committee in 2008 for the use in medium span bridge applications.
Project Description.
This project consists of complete replacement of the New Bridge located on Route 103 over the York River in the town of York, ME.
A new seven span, 510 foot prestressed concrete bridge (55'-80'-80'-80'-80'-80'-55') replaces the existing 17 span steel girder bridge.
MaineDOT elected to move forward with two prestressed concrete superstructure options:
1.Newly developed NEXT beam. Typical section consists of four butted NEXT36 beams with 9'-4 ½" flanges. Weight of NEXT Beam = 1412 plf
2.NEBT 1000
Typical section consists of five NEBT1000 spaced 8'-3" center-to-center.
Weight of NEBT = 778 plf.
The existing timber abutments will be replaced with an integral abutment consisting of a concrete stub abutment supported by steel H-piles with a permanent steel casing to allow piles to remain elastic.
The existing timber pier bents will be replaced with concrete filled steel pipe piles with a fusion bonded epoxy coating.
The new typical section consists of two 11 foot lanes with 4 foot shoulders and a 5 foot sidewalk. The out-to-out width is 38'-2" with steel bridge railing on each side.
This bridge was designed in accordance with AASHTO LRFD Design method.
Challenges.
Developing a new bridge configuration that maintains the existing profile, navigational clearances, and avoids conflicts with existing substructure locations.
MaineDOT desired an integral bridge design for this 510 foot bridge. Project specific details were developed at the abutments to accommodate the design movements.
Dual superstructure designs with a common substructure design..
Next Beam Superstructure Details
Of the five bidders, four chose the NEXT Beam option and one selected the NEBT option.
NEXT Beam concrete strength: f'c=9 ksi, f'ci= 7.5 ksi
Diaphragms are located only at the beam ends at the abutments and piers. No intermediate diaphragms were required.
NEXT beam follows the cross slope of the road. Pier caps are formed to match beam cross-slopes.
NEXT beam provides approximately 4"of additional navigational clearance compared to the NEBT option.
To learn more about the NEXT beam schedule PCINE's new Lunch and Learn on
Accelerated Bridge Construction.
Project Stats:
Owner: Maine Department of Transportation
Contractor: CPM Constructors, Free Port, Maine
Designer: VHB - Vanasse Hangen Brustlin, Inc., Bedford, NH
Precaster: Dailey Precast, Shaftsbury, VT
Project: York County, New Bridge over York River
Bridge No. 3202
Schedule: Installation Spring 2010
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