Newbridge Road Bridge

Client

Neath Port Talbot County Borough Council

Project Description

Newbridge Road Bridge is a Grade 2 listed structure which spans over the River Afan in Port Talbot, South Wales. The bridge comprises three spans, two outer spans of 23m and a central span of 24m, formed of primary box girders supporting transverse steel deck beams and a concrete deck. Constructed between 1899 and 1903, anecdotal evidence suggests that the primary girders of the two outer spans are second hand, having previously been used in a rail bridge. These girders are wrought iron compound box girders, where the top flange takes the form of a box itself, an uncommon form of construction of which few examples remain. Structural inspections have identified that significant parts of the bridge, particularly the steel elements including both the main box girders of the central span and the transverse deck beams throughout the structure, are severely corroded. Cass Hayward, in conjunction with Mann Williams, undertook an options appraisal to explore how the bridge might be repaired or partially replaced. Seven options were explored.

Cass Hayward Role(s)

  • Options appraisal for repair and partial replacement of historic Grade 2 listed bridge.
  • Inspection of interior of the listed wrought iron box girders using borescope to provide confidence that they can be repaired and reused in the redevelopment of the bridge.

Project Statistics

  • Grade 2 listed bridge crossing tidal section of River Afan.
  • Three span structure of approximate total length 70m.
  • Options appraisal for repair of the bridge.
  • Preferred option includes reuse of the existing wrought iron compound box girders.

Special Features

  • Unusual wrought iron compound box girders in end spans of bridge which were thought to have been constructed in the 1850s or 1860s and initially incorporated in a railway bridge prior to being reused in 1903 at Newbridge.
  • Borescope inspection of interior of historic wrought iron box girders to better understand condition and provide confidence to client that they can be reused.
  • Soffit of bridge inspected from pontoon on section of tidal river.