The EARPS shaft was the 4th shaft of the CVB JV East Project to be installed. The EARPS site is also the tightest and the most congested site of the project. Following the same diaphragm wall construction methodology as the other sites, the EARPS Team has the additional challenge of a much smaller working environment.
For lifting the reinforcement cages, normally performed by a tandem lift, the EARPS Team had to think outside the box. The team developed a dolly system which allowed the reinforcement cages to be lifted without the help of a second crane. The dolly system was developed in house by the Soletanche BachyTeam and partly manufactured in France and in the UK.
The lifting device was then sent to our reinforcement supplier yard where a full-scale trial was completed. The whole lifting Team was involved in the trial and an actual cage for the future EARPS Dwall was lifted.
The lifting team also tested the ability of the dolly to retrieve a cage from a panel – in case of an issue inside the open panel – bringing the cage from vertical position to horizontal position. After a successful trial, the lifting team carried out a valuable de-briefing, gathering all comments from the crane operator, slinger/signaller, crane supervisor and appointed persons. The lift plan used for the trial was updated to suit the EARPS site.
The dolly system which was initially developed as a space gain also turned out to be a cost effective solution that could become the norm in similar future operations.