"The wall that required strengthening is right in the centre of the building," said Des Allred, Site Manager for Mainzeal. "Access to the formwork was restricted with limited access and no ability to conventionally vibrate and compact the concrete."

The design team decided to utilise the properties of Firth's Self Compacting Concrete (SCC) to provide a high, early strength concrete into an extremely confined and congested series of forms and to also meet the engineers performance criteria.

The pour itself was complicated by the need to provide safe shelters for the various teams involved in the event significant after shocks occurred that could create further damage and risk to the teams on site. Thankfully these shelters were not required.

"We poured from one end over a distance of 5m as Firth's SCC is self-leveling," adds Des. "Both sides of the wall were poured at the same time and the concrete had to go through 60mm core holds that the tie bars went through. There were no air bubbles and the finish was very smooth. It is a great product and I would certainly recommend its use again. It worked extremely well and we are very happy with the result."

"The concrete performed well reaching between 70 and 80 MPa, more than surpassing the 50 MPa design requirement," said Dominic Sutton, Regional Sales Manager for Firth. "As a consequence Mainzeal have now stabilised the building and can carry out further assessments in order to allow the owners to return to a safe structure."