Having identified that stitch repairs were required to the cast iron piers to Hungerford Bridge, Network Rail required the development of a safe system of work which would avoid disruption to the operational railway above, the navigable river channel below and eliminate the risk of polluting the water course.
Working collaboratively with Network Rail and their Framework Contractor, Costain, CAN designed, developed and gained approval for a bespoke access and containment system which encompassed the columns of the piers – Ring CAN-Span.
The safe system of work required CAN to carefully manage a specialist sub-contractor who undertook the crack stitching, as well as coordinating the river access via barge and working launch.
CAN technicians assembled the Ring CAN-Span on the deck of a barge. Having already accessed the bridge soffit by traversing from the adjacent Golden Jubilee Footbridge, they then lowered the necessary winch cables from above. Upon connecting the winch lines to the Ring CAN-Span system it was then hauled into place, complete with integral containment sheeting.
Each day the multi-disciplinary team were transferred by safety boat to the barge. They were then winched up from the barge to the Ring CAN-Span using a powered ascender system or stepped from the barge onto the Ring CAN-Span if it was at water level. Any subsequent vertical movement was provided by the Span winching system itself.
Throughout the course of the works the navigable river channels remained open and there was no disruption to the operation railway above. The following link shows the early stages of the project, with the building of the Ring CAN-Span and it then being winched into place: http://www.can.ltd.uk/news/hungerford-bridge-access-provision
Duration: 8 Weeks
Location: Central London