Accurate Live Measurements for Shaft Alignment During Sinking or Shaft Remediation


Gabino Preciado Paz, Golder Assosiates

Accurate, easy to obtain, and reliable methods of measurement are the cornerstone of shafts and tunnels development - during their sinking, and at other points of their operation, maintenance or in some cases, remediation. This paper presents a new methodology to capture the present shaft conditions in such a manner that they can be taken from the physical world to the digital, where they can be stored and used for engineering design purposes in a space not directly affected by the costs associated with shaft time and sinking performance. The methodology utilizes the basic principles of the shaft alignment (plumb lines and survey instruments) while adding modern LiDAR, geolocation and survey control tools that can more completely capture the surrounding environs. The complete cycle of collection, through to processing and delivery of pertinent information underground can take under an hour. During sinking, capturing data as a live stream measurement and being able to assess the alignment of the shaft liner can be critical to the design (or redesign) of infrastructure with very tight tolerances – maximizing space and conveyance travel. Minute changes in alignment can be captured as the sinking progresses such that actions can be taken immediately to correct out of tolerance alignment or liner deviation issues which ultimately could affect the final furnish after the shaft is finished. Likewise, post-construction, optimal operating conditions and maintenance for the life of this critical access to the mine can be recorded and digitized. Observed changes can be identified and planned as future shaft repair works, or changes in the design, to make full use of the installed shaft infrastructure. The methodology has been developed and successfully deployed during the on-going sinking works of the Shaft at the Jansen Potash Project in south-central Saskatchewan and is described in greater detail in this paper.
Keywords: New methodology, shaft, tunnels, alignment, remediation, measurements