Wood Crib Design & Mine Roof Support

Objective: To minimize support costs and to improve ground control by improving wood-crib design and utilisation through the development of engineering methods that will match the placement and performance of the wood cribs to the load conditions imposed by the mine environment. Background: While wood cribs are used extensively to stabilize mine openings, their utilization is often … Read more

Rock Drag Cutting

The Bureau of Mines, in its continuing efforts to improve productivity and enhance the workplace environment of hard-rock underground mines, has investigated mechanical excavation techniques and in particular drag cutting techniques to achieve these goals. Two fragmentation techniques that use drag cutters have found some success in the mining industry: the kerf-core technique and, the … Read more

Tailings Backfill

This report presents a study of three typical tailings samples as potential cemented backfill in underground mines. The testing series was unique in that the pulp densities of the samples were all above 75 pct solids. Test results included dry density; slump; percent settling after 28 days of curing; tensile strength after 28, 120, and … Read more

Longwall Pillar Design Method

The past decade has provided a wealth of practical experience with longwall pillar design. Design formulas developed specifically for longwalls have proven their value in numerous applications. Analytic methods, including numerical models, have also made important contributions. These advances have been based on basic research into abutment loads, coal pillar mechanics, and the interaction between … Read more

Mining Methods VS Underground Crusher Location

In Section 2 we dismissed those “big-room” applications not needing fundamentally new equipment, and lumped all the rest together. Now, as we examine specific mine types, it is appropriate to differentiate within these categories the manner in which portable crushers might be used, and the consequent effect on desired machine parameters. The common yardstick by … Read more

Longwall Mining

I was requested to write an article on Longwall Mining a short time ago; however, the time has been so short that I have not had time to prepare an article as I would like to have presented it to this body. In writing this article it has not been my intention in making comparison … Read more

Diamond Drill Sampling Methods

In diamond-drill work, a true sample consists of all the material cut by the bit—both core and cuttings. As the recovery of this sample is the object of diamond drilling, the utmost care should be taken to secure it. Speed of drilling and low costs are of little value if an inaccurate sample is obtained. … Read more

Accounting for Small Mining Operation

The observations here presented are not those of an expert accountant, but of one who, while he has seen considerable service in the accounting departments of large companies, has spent more time in engineering and operating. This paper is intended to cover, in a measure, mine accounting for small mines, as distinguished from the elaborate … Read more

Underground Mining Methods of Zinc Ore

The varying physical character and large extent of the Broken Hill lode necessarily involve the employment of a variety of underground methods. The lode had its origin in an extensive fault plane traversing metamorphosed schists conformably, as a rule, with their beds of stratification. The underground waters carrying minerals in solution deposited their contents in … Read more

Underground Mining Methods of Copper

The system of stoping as practiced was eminently satisfactory to supplement the steam-shovel operations without injuring the ore reserves of the property through a mixing of capping with ore. It had the advantage that all ore produced was absolutely free from waste, since both stopes and development drifts were discontinued when capping was reached. The … Read more