UQ student delivers new insights into shotcrete resistance to fire made of synthetic aggregates

31 January 2023

An undergraduate civil and geotechnical engineering student at The University of Queensland (UQ) has generated promising insights into fire resistance of shotcrete mixes made of waste glass in response to the shotcrete industry's cost crisis.

Due to the increasing cost of sand, the shotcrete industry has been exploring alternative materials to replace sand, making Lee's research findings particularly relevant.

Bachelor of Engineering (Honours) student Yuk Ping Lee focused on the effect of fire-induced spalling resistance of a newly developed shotcrete mix using crushed waste glass (CWG) as a synthetic aggregate.

In his research thesis, supervised by Dr Mehdi Serati and Dr Harry Asche, Mr Lee found that the CWG shotcrete mixes showed no to little fire-induced spalling under extreme heat conditions, suggesting that CWG shotcrete mixes could have reliable performance in tunnel fires.

"During my project, I realised that my research topic is quite controversial as researchers usually had different opinions, and sometimes reach different experimental results and conclusions about the same research questions,” Mr Lee said.

The use of shotcrete, a pneumatic concrete that is sprayed at high velocities, has gained attention for ground support in mines and tunnels worldwide.

“I am very grateful for the opportunity to learn from industry professionals, master's and PhD students, and develop my time management, teamwork, and presentation skills," Mr Lee said.

Mr Lee was selected as UQ’s student representative and presented his research outcomes at the Concrete Institute of Australia’s Student Presentation in late 2022.

UQ congratulates Mr Lee and his advisory team on their ground-breaking research, which offers a potential solution to the shotcrete industry's cost challenges while ensuring the safety and reliability of ground support in mines and tunnels worldwide.