Project Description

An earthquake damaged 13-storey tower building was saved from demolition and repaired. The innovative design and strengthening techniques converted the original design to a rocking wall structure that meets current building code seismic standards, while retaining the original building aesthetics. The strengthening solution employed damping devices retrofitted to the existing structure, in conjunction with a new 37m-long post-tensioning system. The engineering team overcame significant uncertainty around design and constructability to integrate damping devices into the building, along with other elements of seismic strengthening, all made possible through complex temporary works and project sequencing.

Judge’s comments

An innovative project demonstrating the first use of a novel damping device on a reinforced concrete building. The daring seismic strengthening efforts of the engineers enabled the retention of an existing structure that would otherwise not meet current seismic codes. Instead of opting for a simpler demolition and rebuild, the engineers implemented a system to enhance resilience by allowing the building to dissipate energy and reduce structural forces, creating a rocking plane by cutting the structure off at podium level. Changing the stability system significantly reduced embodied carbon, as compared to demolition and new build. The engineering team involved early engagement with contractors and used 3D printed prototypes to check construction sequences.

Project overview

Structural Designer

  • Structure Design Ltd & Phoenix Consulting Ltd

Client Name

  • Russell Property Group Ltd

Location

  • Christchurch, New Zealand

Architect

  • Wilson & Hill Architects Ltd

Principal Contractor

  • Dominion Constructors Ltd

Key Contractors

  • Tectonus (Seismic damping devices)

    Geotech Consulting Ltd (Geotechnical engineer)

    Bradley Seismic Ltd (Site specific seismic hazard analysis)

    Thermosash NZ Ltd (Façade engineering)

    Macdonald Barnett Ltd. (Fire engineering)

    Lewis Bradford (Structural peer review)

    GHD Ltd (Hydraulic design)

    Aquaheat NZ Ltd (Mechanical design)

    C&L Electrical Ltd (Electrical design)

    Contech (Post tensioning specialist)

Year Submitted

  • 2024

Submitted By

  • Russell Property Group Ltd

Key attributes

  • Planet, Process