CASE STUDY: Earthquake strengthening of Church
An historic church gets some much needed support.
CUSTOMER: St Mary’s of the Angels, Wellington
PROJECT: Replacement of Gothic Columns
Designed in 1918 by Frederick Jersey de Clere, Wellington’s St Mary’s of the Angels is believed to be the world’s first reinforced concrete gothic-styled church.
The church was closed after earthquakes in 2013, re-opening three years later following a $9.5 million re-strengthening project. This involved the introduction of replacement gothic columns to support the structure.
These new columns had to precisely match the existing set – an achievement requiring an innovative approach.
It began with 3D imaging of the existing portals and columns. They were scanned to millimetre tolerances with a high-tech, point-cloud scanner to create a 3D model.
Rubber moulds were developed from the 3D models, boxed up on four sides and filled with high-strength, self compacting concrete.
The new additions look identical – in style and texture – to the existing columns, but also feature rods of reinforced steel and ties into new ground beams, making them vastly stronger. Most visitors marvelling at the restored interior think the new portals and columns are original.
St Mary’s passed its first big test with flying colours – a 7.8 magnitude earthquake in November 2016, soon after the structural works had been completed. Engineers couldn’t find a single crack.
Wellington has around 600 earthquake-prone buildings and many owners are looking at St Mary’s as an example of what can be achieved.
What our customer had to say:
“ The team at Jackson were exceptional to work with. The columns at St Mary’s were one of the more complex elements to construct, but with the help from the Jackson team, as well as the point cloud model of the building, the columns were replicated identically to the old. A job well done!”
Matt Pattinson – Site Manager, LT Mcguinness Ltd
Press for this incredible project:
Stuff: “St Mary of the Angels church wins award for seismic strengthening” 20 May 2018
Society of Mary: “St Mary of the Angels church wins national heritage and restoration building award” 21 May 2018