A&K Geotechnical Engineering --> project sheets --> Twickenham footwall access tunnels
Project:
TWICKENHAM FOOTWALL ACCESS TUNNELS
Owner:
Anglo Platinum Co.
Client:
C.M.C. Cooperativa Muratori Cementisti
Project description:
The two tunnels are to provide access to the chromitite ore deposit of the Twickenham Platinum Mine. Each 5m-diameter tunnel is approximately 7km-long. The excavation of the two tunnels by TBM is meant to reduce the time to access the mineral deposit.
Geologic context:
Very hard rock mass consisting of mafic and ultramafic intrusive rocks. Norite and anorthosite are the prevalent lithotypes with compressive strength up to 260MPa. Poorer conditions are expected for the dolerite dikes.
Location:
South Africa
Start/end date:
-
Cost estimate:
-
Design and consultancy services:
TBM feasibility evaluation: Using four TBM performance prediction methods (CSM, Alber's strength-to-stress ratio, NTI, and Barton's QTBM) the feasibility of excavating the tunnels by a 4.94m-diameter Robbins double shield TBM was assessed in terms of advance rate and cutter consumption. Rock support requirements were defined in accordance with the NORM 2203/1994.
Period:
2003
In collaboration with:
SEA Consulting Srl
