WB-207 & WB-208 Bridge Replacements in Beaver County, PA
Pennsylvania Turnpike Commission – Brad Updegrave, P.E. Project Manager
2016 Outstanding Highway Engineering Award
$5M to $15M Category
American Society of Highway Engineers – Pittsburgh Section
CDR Maguire, Inc. was retained by the Pennsylvania Turnpike Commission (PTC) for design services on the Beaver River Bridge (BRB) Replacement Project in Beaver County. The project consisted of the relocation, widening, and full depth reconstruction of approximately two miles of I‑76 from MP 12.02 to 14.01, the reconfiguration of the Beaver Valley Interchange, and the widening of SR 0018 at the interchange. The total reconstruction widened I-76 from its existing 4-lane typical section and 78’ width, to a 6-lane typical section plus eastbound and westbound on/off ramps for a total width of 146’.
In the Fall of 2011, the PTC decided to replace the existing Norfolk Southern Railroad WB-207 Pony Truss and WB-208 Thru-Girder Bridges over I-76 as an Early Action Contract to the Mainline Widening Construction. The WB-207 and WB-208 Bridges act as the west and east legs, respectively, of the “Wye” connection from Koppel to the Fort Wayne Line from Pittsburgh to Chicago. Norfolk Southern required that one leg of the Wye always remained in service during construction. An added stipulation is that the combined track outage had to be less than 22 months. The proposed option relocated the WB-207 Bridge between the existing WB-207 and WB-208 Bridges, using a 12° curve, and maintained the existing WB-208 alignment. Thru-girder structures were utilized for both replacement bridges. The WB-207 (MP 12.63) and WB-208 (MP 12.67) structures are near the WB-209 Bridge over SR 0018 (MP 12.83).
|Replacement Structure Data||WB-207||WB-208|
|Span||156’-7 ¾” Span 1
90’-2 1/8” Span 2
|99’-8 1/8” Span 1
76’-8” Span 2
|Skew||39°21’56” Span 1
56°57’13” Span 2
|84°40’38” Span 1
79°03’33” Span 2
The bridges were designed using the ASD Method, in accordance with AREMA. Additionally, Norfolk Southern required the use of all bolted connections and ballasted deck plates. Due to the requirement for all bolted connections, great care was taken in the geometric layout of the floor beams, knee braces, angle stiffeners, flange to girder connection angles, field splices, deck plate, and ballast retainer to avoid member interference and to provide bolt clearance. The final design required over 187,500 holes.
In a letter from the PTC, Jim Stump stated, “The Commission was pleased with the engineering services provided by CDR Maguire’s team as they prepared the design for these very complex structures required to carry Norfolk Southern Railroad Loads. CDR Maguire delivered an economical bridge design in a timely manner.”