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One of the essential issues of the benches’ development procedure is the choice of the method of seam development in the complex structure: joint development of rock and coal seams in one complex face or their separate excavation in blocks of 50-100 m in length. The decision of this question is connected with the mode of mining works, represented by the schedule of stripping and winning works. The choice of one or another method is connected with operative-dispatching control of haul trucks delivery. When rock and coal are mined together in a complex face, overburden haul trucks should be supplied for loading rock and coal haul trucks for coal in turns. It is organizationally difficult to supply haul trucks of different purposes during the shift. It is necessary to proceed from the shift (daily) planning of haul trucks supply for specific faces. In addition, it is necessary to take into account that rock and coal faces are often located on opposite sides of the quarry pit. This article studies the issue of organizing the operation of excavation and loading equipment during the mining of the coal-bearing zone of the open pit in order to reduce the loss of output of haul trucks.

Hydraulic excavators currently used at open pit mines, in particular backhoes, are more maneuverable, mobile and have more digging capabilities than rope shovels. This makes them suitable for a variety of conditions: top and bottom digging, loading lower, higher and at the standing level. The variants of mutual arrangement of the excavator and the dump truck, respectively, affect the duration of the excavator cycle, which, in turn, directly affects the productivity of the excavator. This article evaluates changes in the productivity of an excavator, depending on its angle of rotation and options for digging and loading. It is determined that the smaller the swing angle of an excavator, the greater its impact on productivity. Based on the executed calculations relative decrease in productivity (in percent from the most optimum variant) is established. Results of work can be used at planning of open pit mining for the purpose of definition, for example, speed of mining front movement at change of parameters of an excavator face and a type of a digging and loading.

As is known from the classic works on open pit mining, the bench is a separately developed part of the rock layer, having the form of a step. It should also be noted that it is necessary to clearly differentiate the concepts of “bench height” and “height of the layer to be removed.” The benches are often divided into subbenches, developed by different excavation equipment or by the same equipment both sequentially and simultaneously, but having transport routes that are uniform for the bench. As an example, an excavator stripping of the upper and lower subbenches with loading, respectively, at the level of the excavator and above this level, is usually given, that is, the transport route (road) passes through an intermediate platform bench located in the middle of its height. Therefore, the excavation layer of any height, which is, in fact, a part of the working bench, can be considered as an independent bench with all its attributes, but in order to avoid duplication of definitions, this paper suggests the name “extraction layer”. When developing this element various digging modes can be applied. In this paper, we studied the main modes and selected the one that provides the highest performance.

Currently, two types of handling machines are mainly used on coal open pit mines in Kuzbass, characterized by complex structural deposits: mechanical (rope) and hydraulic (backhoe) shovels. Moreover, both types of equipment are supplied to the quarries: mechanical shovels are purchased, as a rule, powerful with a bucket capacity up to 56 m3, backhoes – small and medium-size models with a bucket capacity of 2.8-14 m3. On the other hand, it is common to divide the areas of equipment use in the open pit on complex-structured deposits into a coalless (outside the strata of coalbeds) and coal-bearing (actually a series of beds, including coal strata and rock interbeds). The use of these equipment types in both design and industrial practice is observed in both zones. At the same time, it is known that each of these zones has different conditions for the efficient operation of excavation machines. The seams, therefore, do not complicate the coalless zone when working in it, favorable conditions are provided for the excavator: the constant height of the bench, which is necessary for the full filling of the bucket for one scoop, the constant width of the panel and the length of the front of the work. In these conditions, the maximum productivity of the excavator is ensured.

Numerical simulation of bulk technogenic rock arrays, unlike the full-scale, has a number of advantages. They are: the large amount of low cost measurements; operative selection of parameters necessary for the environment with the given properties; calculation of stress-strain state and assessment of the array sustainability; calculation of rock arrays filtration properties that are used as filters for mining enterprises sewage, etc. The article describes the method of numerical simulation of structure of bulk disjointed rock arrays, describes the basic initial and boundary conditions of the model; represents the numerical model visualization of the array, created with the use of peripheral dumping (as an array with more textured and visual segregation of granulometric composition adjustment). The basic applications of numerical modeling of technogenic rock arrays in the mining processes are described. Comparative analysis of the real and simulated array structure shows the adequacy of the numerical model and the developed for its creation algorithm, which in turn allows judging the quality of the study. Also, the adequacy of building models is supported by a high convergence of the experimental and calculated figures depending on the filtration rate values of the particle size distribution of technogenic rock arrays.

Features of geological structure of the Kuznetsk coal basin stipulate the application of a low-cost open technique of coal mining, which is more advantageous both from the economic standpoint, and by safety criteria of mining. However, open mining affects significantly the water resources of region. Intensive pollution of reservoirs and water courses, exhaustion of the underground water-bearing layers, violation of a hydrographic network, etc. be-long to the main disadvantages of an open technique of coal mining. Besides, the volume of the water coming into the mining producers exceeds signi-ficantly the needed quantity. According to the data of annual reports of ecology and natural resources department, 348.277 million m3 of water were ta-ken away during production of soft coal, brown coal and lignum fossil from waters of Kemerovo region in 2013 (mostly from underground water objects (96,5%) when draining of mine openings). At the same time, only 87.018 million m3 of water (25%) has been used within a year.

The examples of mining rock panels by different types of equipment are given in this paper. In such conditions, it is most expedient to use wide stopes to improve the productivity of equipment by reducing the time for auxiliary works. Also technological schemes of equipment operation in different conditions for several quarries of the Kuzbass are proposed. The coal-bearing zone is worked “layer by layer” with one or two benches or subbenches. The bottom of the quarry in this case is flat, without leaving “peak” of overburden rocks in the pillars. Cutting of the benches is carried out by trench with a wide bottom on the side of the roof of the coal bed and simultaneously working it with the same excavator or with setting up a additional excavator for coal mining operations. Interbeds are mined out with the use of wide stopes, often to the theirs entire horizontal width. Complex rock-and-coal blocks, including one-three coal beds, are also worked out by wide stopes.