Can’t afford the latest CIM collection of technical papers? It’s now on sale for $150. Here is how I got the information from a paper, the title of which caught my eye. The title is “Using Simul8 to model underground hard rock mining operations.”
A quick Google search took me to this site where McIntosh writes:
“A typical example of a [Simul8] computer simulation in underground mining would be a scenario involving multiple Load Haul Dump (LHD) units transferring ore from a source location (stopes or draw raises) to one or more ore passes. An engineering evaluation would be completed to determine the optimum number and size of LHDs required to transfer a specified ore quantity over the course of a particular time period (shift, day, week, month).
With certain limitations, it is possible to solve this problem with a spreadsheet. Cycle times can be determined based on alternative speeds, loading times, and tramming distances. The spreadsheet solution does not allow one to easily determine (with high confidence) the impact of multiple LHDs operating simultaneously.
If one LHD can handle a given tonnage of ore in a single shift, can two LHDs transfer double the quantity? Can three LHDs transfer three times the quantity? Of course the answer is no, two or more LHDs working simultaneously will encounter interference delays resulting in reduced productivities. Performing the evaluation with a spreadsheet requires the engineer to estimate an “interference factor.” The more units of equipment operating, the greater the impact of the interference factor.
The engineer’s problem is that no one has an instinctive feel for an appropriate interference factor. While we may have a good feel for factors such as loading, dumping, and travel times (based on the actual mining conditions), we do not have an instinctive feel for interferences.
They describe three case histories of the application of Simul8 in underground mine operations. These case histories deal with: (1) Underground Storage Bins; (2) Underground Truck Haulage; and (3) Block Level Cave Draw and Haulage Optimization. Bravo the freedom of the internet!
