Formerly the world’s longest suspension bridge, the Humber Bridge spans the Humber Estuary from East Yorkshire to Lincolnshire across a 1,410-metre roadway. Wear and tear caused by 32 years of strong weather conditions necessitated the replacement of the A-Frames, which connect the deck to the towers and allow the bridge to expand and contract naturally in the heat and cold.
Following design optioneering, Spencer Bridge Engineering’s innovative scheme was selected to replace the main span’s A-frames with a pair of vertically orientated pendels and a wind shoe at each tower, thus separating out the horizontal and vertical forces, with benefits for construction and maintenance. This would not only replace the existing A Frames, but also reduce the stress on the new replacement to increase its lifespan and reduce the cost and frequency of maintenance. The project was a complex scheme involving several engineering disciplines. This included working at height in a confined below-deck area, whilst minimising the effect on the bridge’s operation as a vital artery and Hull’s only fixed crossing.
Spencer Bridge Engineering successfully implemented a new main span A-Frame replacement system that ensured the integrity of the bridge and simplified future maintenance.
Using their in-house design resources, Spencer Bridge Engineering were able to create an end product that was highly praised by the client. As well as the design being highly innovative, the delivery approach of the project allowed the team to keep the bridge operational while works were carried out, leading to an ongoing positive relationship with the client.
Due to the successful delivery of the project, Spencer Bridge Engineering won the Civil Engineering Project of the Year (up to £10m) category in the British Construction Industry Awards 2015, the 2015 ICE Smeaton Award and was nominated for the Prime Minister’s Better Public Building Award. The project also became the subject of a paper produced by the Institute of Civil Engineers (ICE).
