Bridge Rehabilitation and Replacement

SAI is responsible for the final design and construction consultation of a project that includes 1,500' of roadway approach on S.R. 3007 and the replacement of an existing bridge over Redbank Creek in Jefferson County, Pennsylvania.


Physical Features: 
  • 198' three-span continuous steel multi-girder bridge over Redbank Creek.
  • Deck consists of two 10' lanes, 4' shoulder, and 5' sidewalks on each side of the structure for a deck area of approximately 5,544 sq. ft.
  • 1,500' of roadway approach realignment on a two-lane rural minor collector with an ADT of 936.
Other Features: 
  • Structure grade changes from tangent to vertical curve at the end of the bridge with a maximum slope over 8%.
  • Substructure components consist of tangent caisson (abutment 1), concrete cantilever (abutment 2), wall-type piers on spread footings (piers 1and 2).  Permanent steel casings without concrete facing were used for abutment 1 and required grouting holes behind the caissons to close the gap and prevent soil migration.  Using a tangent caisson cost less than a cantilever abutment and minimized vibration.
  • Traffic maintained via phased construction of structure on new alignment.  Short-term 5 day detour necessary for the approach roadway work south of the structure.
  • Erosion and sedimentation control plan.
  • Permit acquisition and agency coordination.
  • Signing and pavement marking plan.
  • Utility design and coordination.