Christ Church Cathedral

We provided early contractor involvement (ECI) services and acted as the main contractor for the stabilisation and strengthening stages of the Christ Church Cathedral Reinstatement.

We worked closely with the structural engineering consultant to plan the structural sequencing and detailing of the massive steel frames during the stabilisation phase. We also effectively managed sub-consultants to provide structural temporary works designs for steel lift planning, propping and mitigation of local stability hazards. We were on site for almost three years before the Cathedral was safe enough to enter, with all work up to that point completed from a safe distance outside the structure. Even the clean-up of 250 tonnes of rubble and biohazards was accomplished using a remote-control digger, a world-first that was suggested, investigated and implemented by our team.

The next phase involved careful recovery of heritage items, followed by strengthening the superstructure in preparation for new foundations. This required new reinforced concrete walls to be cast within the width of the existing walls. We managed the design and installation of further significant temporary works, then partially deconstructed the walls so they would remain stable while we installed reinforcing and poured concrete against the remaining stone. Other methods used to strengthen the unreinforced stone walls included embedding structural steel sections and injecting grout into the voids before pinning the internal to external stone with stainless steel pins.

We were about half-way through the strengthening phase when the project was paused until funding could be secured.