Vol 19

Conceptually, the task of surveying measurements is simple, however, its practical solution, provided that the necessary accuracy is ensured, in a number of cases becomes complex and requires the use of special techniques. This task becomes especially difficult in the conditions of deposits of non-metamorphosed platform-type coals, characterized by a complex structure of seams, variability in thickness, ash content and volumetric weight, and intense weathering of coal during storage in piles. In 1944, we carried out work to study the issue of surveyor measurements at the Cheremkhovo field (Irkutsk basin), which is a field of this type. The results obtained, which we want to share in this article, can be successfully used in a number of other fields. Since during surveying measurements under the conditions under consideration the most difficult thing is to accurately determine the volumetric weight of coal, we will focus on the results of our work on this issue.

The article deals with the question of expediency of exploitation of many portions of Cheremchovo deposit by open-pit mining. In the transition to open-pit methods of work the losses of coal are diminished by 30—35%. This makes it necessary to reconsider the methods of exploitation of this deposit.

The problem of determining stresses in lifting ropes and the question of longitudinal vibrations of elastic rods, related to it in formulation and methods of solution, have a long history, set out in a recently published monograph by Prof. A. S. Lokshin. As early as 1815, Poisson studied the free vibrations of a prismatic rod with a weight at the end. Without setting out to list all the works that were closest in time, we note Boussinesq’s research on the impact of a body of a certain mass on a conical rod of infinite length, as well as the memoirs of Saint‑Venant, who studied the impact of two prismatic and conical rods. The same authors also considered, among other related issues, the question of longitudinal vibrations of a rod with a load at the end. The main results of these authors are presented in the famous book by A. Love.

The author declares this as a most expedient an independent classification of stopping methods for ore mining. The best classifications of mining methods are based upon methods of support. The author proposes a classification of ore mining methods adopted by the Mining Division of the Bureau of Mines U. S. A. with a few changes and complements in accordance with our mining practice and order for describing methods in leading Russian mining schools.

In the present work it is noted that the speed of stope advancement is important not only regarding the increase of output of some or other sections of the shaft, but it is also important concerning the safety of work, facilities of roof control and also the economy of timber expenditure. The review of the problem of underground mining of orebodies leads to the conclusion that the speed of stope advancement is the factor which plays the most important role in the exploitation of the given orebodies. The increase of the speed of stope advancement when the selection of the method is correct makes conditions favorable at the mining of close-set layers. Profitable results at the mining of some orebodies in many cases are got exclusively due to the high speed of stope advancement.

The existing classifications of bulk loading machines are based on external features and, being formal and one-sided in nature, do not allow revealing all the features of various designs. The proposed classification is based on taking into account the entire complex of conditions affecting the shape and operation of machines. It takes into account the organization and technology of processes accompanying bulk loading; design features of machines capable of performing operations in one action or in parts; and other natural conditions. Therefore, it opens up wide opportunities for improving old and creating new machines, as well as for improving the way they are used.

The Bukuk deposit is situated in the region of development of middle Jurassic marine deposit, Variscian granites and Post Jurassic granodiorites. The granodiorite intrusion probably corresponds to the pre-cretaceous folding having highly marked traces of activity in the Eastern Transbaikal. The forming of the ore in this region chiefly takes place in the granodiorite massif, in its central and endocontact parts. The orebodies are very seldom found in the sandy-shale masses of rocks. In the course of the genetic study of the Bukuk orebody it was found out that in the formation of the orebodies the magmatic solutions used the well developed fissility in the granodiorite. In the moment of the cooling of the latter, many joints of different directions were formed. Later on they were opened and changed into gently sloping or steep fissures of diaclase, which subsequently were changed into fissures of paraclase.

November 2, 1944 marked the 70th anniversary of the birth of one of the foremost specialists in the field of mining mechanics, Academician Alexander Petrovich German.