Clarence Bridge, Regent's Park
HPM were instructed to undertake a full survey of this wrought iron lattice bridge due to concerns that it was excessively corroded. It was clear that the bridge had been poorly maintained and the corrosion had been made worse by an automatic watering system for planters attached to the girders.We determined the extent of corrosion and analysed the bridge to determine the loss of cross section which could be tolerated by each member so that the number of repairs would be minimised in accordance with the conservation principle of minimum intervention.
A repair contract was then let where the bridge was cleaned to bare metal and primed. We were then able to survey all members and determine where sections of the lattices and flange web needed to be repaired. Small sections were cut out and replacements welded in and a number of rivets were replaced using hot rivetting.