Safer and more efficient tunnel drilling in the future

(19-08-2021) When drilling a tunnel in soft ground for the construction of a railroad, for example, it is not always easy to keep the drill stable. In this PhD, Dongzhu Zheng investigates how this stability can be improved.

"To maintain the stability of the drill bit, foam is often added when drilling. In my PhD, I investigate the behaviour of this foam infiltration on drilling in saturated sand," explains Dongzhu Zheng.

"I compared the results of my experiments with data from the Botlek rail tunnel," Dongzhu continues.

This Botlek rail tunnel is the first drilled rail tunnel in the Netherlands and serves to run a freight rail line under the Old Maas River in Rotterdam. The tunnel consists of two drilled tunnel tubes and was put into operation on September 17, 2006.

"In the second part of my dissertation, I propose a new model that predicts the effect of foam filtration on the behaviour of the drill. With my research and new model, I hope to contribute to safer and more efficient tunnel drilling," Dongzhu concludes.


PhD Title: Tunnel Boring Machine Excavation Fluids: From Laboratory to Practice


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Editor: Jeroen Ongenae - Final editing: Ilse Vercruysse - Illustrator: Roger Van Hecke