CIM ends with Paul Hughes intellect and frozen backfill in mining

The Edmonton CIM conference came to a crescendo ending today with a session on backfill and a session on the impediments to progress in mining.  The night before I was invited by a work colleague to the McDonald Hotel and its Harvest restaurant.  This is one of those grand hotels built across Canada to provide rail-travellers luxury accommodation as they traversed the country.   And we ate, drank, and laughed well. 

At the dinner was a young man whose parents indulge in a taste like mine for 1970s style orange and green bathrooms.  Seriously though, this young man is, in my opinion, one of those who will dominate the mining industry in the years to come: as much because of shining intelligence as urbane manners and a perfect-pitch sense of humor–afterall if it is not fun, why do it?

To prove my point re intelligence, I asked and received from him, his notes on this morning’s session on backfill, in which he presented a paper based on his master’s thesis work.  Now he proceeds to a PhD, and if I were a betting man, I would bet on him and his thesis. 

The following is written by Paul Hughes, a PhD student at the University of British Columbia, Vancouver.  He and his thesis supervisor, Remus Pakalnis surely are advancing the art of mine backfilling.

The CIM AGM Wednesday, early morning talks for the session “Process Improvement- Rock Engineering in Mining Practice 2″ was chaired by Dennis O’Donnell and Luc Beauchamp. Attendance was sparse, most likely due to the P & H Reception the night before…

The first talk by Kirsti Tarr of CANMET, focused on the effects of the scale of the tested sample on the strength and modulus properties of backfill.  Her talk was interesting as it was a good summary of prior research and an update on the current backfill testing by CANMET.   I have found their results useful in my research.

Dr. Will Bawden of University of Toronto updated of his current research in paste backfill mechanics in long-hole stopes.  Dr. Bawden’s project was a very well-thought-out: he instrumented stopes to monitor an incredible variety of behaviours for both the short and long term. It was disheartening to hear that of the roughly fifteen instrument nests only four survived - instrumenting in underground environments in never an easy task! However, the remaining instruments nest’s initial results were very impressive.

I was the third speaker of the session, discussing the performance of shotcrete/rebar composite fill fences. Started out a bit nervous, but thankfully was able to hit my stride in a few slides in. The talk was a summary of research undertaken as part of my recently completed Masters degree. I was a bit apprehensive at first: I have been fully invested in my research for a while now (maybe too long?) and wondered how it would be received. From the questions posed it seems as if there is interest in the research and I was relieved no one pointed out any flaws.

Finally Daniel Cluff discussed his frozen backfill research study. His talk was informative and his research method pragmatic: basically he seeks to avoid the use and cost of cement to stabilize the backfill and instead get the right mix of rock, tailings, and water and freeze the mix quickly to provide underground backfill support. The sample preparation method used was unique in that the samples were prepared as if they would be in the mine; rough and ready and almost primitive–made with low precision—they wanted to test the material as it would be constructed in the mine. As such, they were able to test the entire range of material composition and determine the possible strength values that would be realized in the stope. This methodology is in contrast to creating perfect samples in the laboratory and hoping all goes well once placement of backfill commences.

I have managed to get the powerpoint slides of Paul’s and Cluff’s presentations and will post them tomorrow on TechnoMine.  [Here is a link to Paul's presentation.]  Take a look for they are, in my mind, both superb examples of innovative and significant research with significant practical implications and cost-saving possibilities.

PS.  The session on impediments to progress in mining deserves a long peice and I will write it tomorrow–stand by for the conclusions are profound.