1. Engineering Research Centre of Rock-Soil Drilling and Excavation and Protection, Ministry of Education; China University of Geosciences; Wuhan Hubei 430074 China
2. Geotechnical Research Centre, Faculty of Engineering; The University of Western Ontario; London Ontario N6A 5B9 Canada
3. Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education; College of Civil Engineering and Architecture, Guangxi University; Nanning Guangxi 530004 China
4. School of Computing, Engineering and Mathematics; University of Western Sydney; Locked Bag 1797, Penrith Sydney New South Wales 2751 Australia