Spencer Bridge Engineering has released images and details of refurbishment works on the historic Menai Suspension Bridge.
The crucial road link between mainland Wales and Anglesey re-opened on Saturday, with work suspended for four months, after completion of the first phase of a repair works programme.
Spencer, which has been carrying out works over the past four years to revitalise the crossing ahead of its 200th anniversary year, began a hanger replacement project in Autumn 2023 after engineers identified a 'structural concern'.
The firm said that, in collaboration with UK Highways A55 Ltd, it has replaced and painted 168 of the 208 wire rope hangers on the 417m-long bridge, restoring the full structural integrity of the structure.
It said that to respect the heritage and historic features of the bridge, it worked closely with suppliers throughout a rigorous period of development and testing to design the specially fabricated hangers and sockets.
The hangers, which range in length from less than one metre to over 14 metres, were fabricated to a stringent specification with a narrow length tolerance by specialist Swiss steel manufacturer Fatzer AG.
To safely remove the existing hangers, which were installed when the bridge was reconstructed in 1938, while protecting the surrounding bridge structure, Spencer’s bridges team also designed bespoke equipment including a de-tensioning rig and pin pusher.
The firm described completion of the hanger replacement programme to schedule as a significant engineering achievement, ‘given the complexity of the programme and the speed with which it needed to be designed, procurement and supply chain challenges, and adverse weather conditions’.
Project manager Tom Inglis said: ‘We have decades of experience working on a range of complex bridge and infrastructure projects, and with a very collaborative attitude, allowing us to utilise expertise from right across the team to deliver the most efficient and effective results.
‘One of the factors which made this project so successful was the close relationships we have developed over a number of years with the client, UK Highways A55 Limited, and our suppliers. Those relationships were especially important to deliver this challenging project on time.’
A spokesperson for UK Highways A55 Ltd added: ‘The Menai Suspension Bridge is an icon of civil engineering and a beloved part of local and national heritage and we are proud to have completed these works thanks to the outstanding leadership of Spencer Bridge Engineering.
‘We hope the pause in works over the winter will benefit local residents and businesses with less disruption and improved access during the holiday period.’
The Grade I listed structure first opened in 1826 and is the second oldest suspension bridge in the world still carrying vehicle traffic.