ABSTRACT
The management of the slurry system in tunneling projects plays an important part in the safety and efficiency of the tunneling operation when using a slurry shield TBM. The bentonite slurry is used for maintaining face stability and transporting the cuttings to surface. This requires continuous monitoring and control of flow rates and density. The current method for measurement of density is by means of a radio-active source and a receiver. The disadvantages of using a radioactive source are numerous, in particular with regard to safe handling and storage of the device. This paper will describe the development of an alternative, non-radioactive method for measuring the slurry density, by using radio frequency waves. The design, system architecture and testing methodology will be presented, followed by assessment of applicability of the meter to the monitoring of slurry density in a slurry shield TBM.
