“The Largest Ground Anchor in the World”- Public Lecture presented via zoom on 10th November 2021 by Dr Nihal Vitharana
The lecturer presented about the design and installation of 91-No. 15.2mm diameter multi-strand ground anchors in stabilising the Canning Dam in Western Australia, involved the largest capacity permanent anchor ever used in the world to date.
Dr Nihal Vitharana
In recent years, he has been working as a geotechnical/durability consultant for most of NSW’s key transport projects including his previous role as the leading independent verifier for 2 Light rail projects. He was also the technical adviser to a contracting consortium involved in the planned raising of the largest dam supplying water to Sydney.
He is a graduate from University of Moratuwa and holds a PhD in structural engineering from University of Canterbury NZ and a ME in geotechnical engineering from University of Sydney.
The design and installation of 91-No. 15.2mm diameter multi-strand ground anchors in stabilising the Canning Dam in Western Australia involved the largest capacity permanent anchor ever used in the world to date.
The Minimum breaking load of each anchor is 2250 tonnes. This defied all the design basis criteria practised in ground and bridge engineering practices. They are anchored 130m into the rock mass. The work was undertaken when the 70m high dam was full of water while drilling only 0.5m away from the water face.
These ground anchors are monitorable and stressable with double-encapsulation in HDPE sheathes. A full-scale laboratory test was undertaken as the margin for error is very small due to the consequences and risk profile associated with the dam’s failure.
Dr Nihal was the supervising structural and geotechnical consultant for the project.