OneSteel Tunnel Shutdown – Concrete Repairs

Infra Build
Sydney NSW
Lindsay and Dynan
Dec 2019

OneSteel Tunnel Shutdown – Concrete Repairs


Freyssinet Australia has been engaged with OneSteel Mini Mill to conduct concrete repair works to an underground duct tunnel used as part of the ventilation system for the mini mill.

Maintenance works were carried out in shutdown periods over Christmas and Easter. Freyssinet has completed seven shutdown projects from 2014 to 2018.

Works included working in a confined space, completing survey assessment of delaminated concrete, hydro demolition to delaminated concrete walls / soffit areas, steel augmentation based on approved design, guncrete works to repair areas and miscellaneous joint sealant works.


Key Aspects: 
Freyssinet was responsible for completing concrete repairs to the underground duct within the shutdown dates allocated to project. This consisted of 24-hour work, usually through weekends and the Christmas period.
Freyssinet was responsible for completing repair works as per the approved design which involved delaminated concrete removal, steel augmentation and guncrete works to specified areas.
Completed quantities: 77M2 of concrete repair and 10LM of joint sealant replacement.