Old Northern Avenue Bridge

Old Northern Avenue (Boston, MA)

Type: Rim Bearing Swing Span
Location: Boston, MA
Client: City of Boston Public Works Department


This project involved the rehabilitation of a severely deteriorated rim bearing swing span. The intent of the design was to return the bridge to an operable condition with the minimum amount of work. Due to the contractor’s concern over the operational reliability of the structure even upon completion of the intended repairs, SBE personnel were retained by the contractor to provide construction engineering services for the rehabilitation.

At the contractor’s request, SBE personnel reviewed the scope of work for reasonableness, performed a preliminary site inspection to verify the existing condition of the components, and developed the methodology for the work in conjunction with the contractor. SBE personnel prepared demolition and rehabilitation plans to identify and detail the following required work:

  • Temporary Restraint to tie off and support the span during the work.
  • Rehabilitation of the Rack Pinion Shafts and Bearings.
  • Rehabilitation of the Rim Bearing Rollers.

SBE personnel provided direct correspondence with the Engineer of Record to refine the intended scope work procedures so as to facilitate the review process and maintain the schedule for the field work. SBE personnel performed all calculations to verify the integrity of the construction methods. SBE personnel provided on-site services to verify the alignment of components prior to disassembly and then to supervise the re-installation of the rehabilitated machinery to ensure that the original alignment was maintained. SBE personnel supervised and provided trouble-shooting of the start-up testing once all work was complete.