The project was for the replacement of some under strength concrete way beams over redundant, partially filled construction shafts in Sapperton tunnel. The original beams were installed in the 1980s to cap off shafts left by Brunel during the original construction. A spare beam held by Network rail was tested to destruction and found to be under strength for the loading on this line.
Tony Gee designed replacement beams to support RU loading. There was a strict restriction of four tonnes per beam due to the lifting capacities of the road rail plant. As a result the beam was designed in three longitudinal sections which were then bolted together with transverse stainless steel bolts once placed.