Companies fined $250,000 after concrete blowout

Two related construction companies have been convicted and fined a total of $250,000 over a dangerous concrete blowout during work on the Melbourne Metro Rail Project.

Adcon Vic and Adcon Resources Vic were found guilty of five charges under the Occupational Health and Safety Act and sentenced ex-parte in the Melbourne Magistrates’ Court.

Adcon Vic was convicted and fined $100,000 for failing to ensure that a workplace under its management and control was safe and without risks to health.

Adcon Resources was convicted and fined an aggregate $140,000 for failing to provide a safe system of work and failing to provide workers with information, instruction and training.

The companies were also fined $5000 each for failing to comply with a requirement to provide information to WorkSafe and additionally ordered to each pay $4054 in costs.

The court heard Adcon Resources provided labour and concrete formwork plant to Adcon Vic, which was contracted to provide formwork and concrete pour works for the construction of Parkville Station in Carlton.

Workers had cast a series of high tensile Z ties, similar to concrete reinforcing bars, into the floor of the underground chamber to support the base of formwork for a single-sided wall.

During the concrete pour in July 2021, part of the formwork failed, resulting in uncontrolled movement of the formwork and release of concrete. Workers stopped the pour and found that one of the ties had sheared off. Without engineering oversight, they removed the tie and bridged the gap with a steel beam.

After the concrete pour was recommenced there were a series of cumulative tie failures, resulting in a blowout of about 15 cubic metres of concrete as workers were evacuated.

A WorkSafe investigation found that the Z ties had been welded to the base reinforcing steel instead of secured with tie holders, and that technical specifications for the ties advised they could not be welded due to their chemical composition.

The court heard that it was reasonably practicable for both Adcon Vic and Adcon Resources to reduce the risk of death or serious injury by ensuring:

  • The formwork was constructed in accordance with engineering drawings;
  • A pre-pour checklist included checking the ties were installed correctly;
  • A third-party engineer inspected construction prior to the concrete pour, including checking use of tie holders as specified in engineering drawings;
  • Bars that weren’t designed for welding were not welded;
  • Concrete was at a suitable temperature and noted on engineering drawings; and
  • That, after any failure of the formwork, an engineer’s advice was obtained to determine a safe response and workers were moved to a safe area.

“A blowout of 15 cubic metres of concrete on a major construction site is incredibly dangerous, creating significant risk to workers and anyone else in the vicinity,” said WorkSafe Victoria executive director of health and safety, Narelle Beer.

“Fortunately, in this case, no one was killed or injured – but it’s not enough to rely on good luck, employers and those with management or control of a workplace must do everything they can to identify hazards and eliminate or reduce the risks.”