Climbing South Quay Plaza's newest tower

South Quay Plaza 4 is the second phase of the South Quay Plaza residential development in London’s financial district, Canary Wharf. Once complete, the newest tower will stand 56-storeys high and comprise 400 residential units.

Following the successful delivery of the first phase in 2018, we were appointed to design temporary works solutions for the complex shape of the core and all the slab work for this tower. Where possible, the solution had to incorporate the customer’s PERI equipment used in the first phase.

Construction started at the peak of the COVID-19 pandemic in the UK — a time when the industry was already experiencing labour and material shortages due to BREXIT.

These unforeseen issues in addition to the complexity of the project meant that site support was crucial. Our demonstrators made regular visits to site, supporting operatives with system installation in line with social distancing guidelines.

The core was split into two climbing zones to achieve the customer’s desired pouring sequence and 6-day cycle time. This enabled installation of rebar and fixings on one half of the core to take place while concrete was poured on the other half.

Hydraulic climbing reduced crane operation, enabling it to be used primarily for transporting reinforcement cages to the working levels. Our fully enclosed climbing solution was made up of 3.3m-high MAXIMO formwork shutters combined with ACS-G to construct the external core walls and ACS-P for the internal walls. Four ACS-P systems were used inside the core, two of which comprised built-in hatches to facilitate pours and the installation of precast stairs. Two smaller ACS-P systems climbed inside the shafts, with suspended PERI UP 75 stair towers providing emergency access to the levels below. RCS bridge platforms were also used to accommodate smaller areas and provide access to the core.

The South Quay Plaza 4 superstructure features a complex and challenging core geometry. With the experience of both teams, we collaborated on design, planning and installation. We used a combined ACS jumpform solution within a tight footprint on site where pre-fabrication and just in time deliveries were key. We utilised PERI’s digital 3D model for planning and briefing. The result was great, as it allowed us to capture the detail and lifecycle of the system from erection to operation to the dismantling stage. The team at PERI were proactive in meeting our needs with engineered safety at the forefront of their solutions, including built-in access hatches and access stairways from top to bottom.

Brad Allen - Project Engineer, Expanded

Another complex aspect of this project was the change in wall thickness throughout the core. Our designers had to adapt the formwork arrangement to achieve 450mm-thick walls up to level 18, reducing to 250mm from level 53 upwards.

The project’s small footprint, proximity to the DLR (Docklands Light Railway), and adjacent South Quay Plaza tower meant that just-in-time deliveries were crucial to controlling storage capacity on site. All external platforms were prefabricated in sequence by our team in Rugby to limit the amount of equipment on site at once and to simplify installation. In total, we prefabricated over 80 elements ready for final assembly on site.

We also provided digital services to support our customer with complex areas of the build. 3D models of the structure were produced to visualise the climbing sequence, enable clash detection, and identify spatial limitations ahead of construction.