When designing and planning quarry operations, the parameters of mining systems are usually based on annual production limits, which naturally depend on the quarry's productivity, initial position and the size of the frontage on the ledges. The consequence of annual production limits are annual limits and volumes of overburden. Lack or excess of the front of mining works, dispersion of equipment and transport communications on many ledges, periodic stops of the front on one of the sides or a group of ledges and concentration of the majority of mining excavators on one or two ledges with a small length of blocks - complicate the work of transport at the quarry and along with other organizational and technological reasons are the result of insufficient justification of the parameters of systems within the quarry.

The labor costs of the main and auxiliary mining processes depend on the number of excavators on the ledge, which determines the length of the blocks and the intensity of the front movement. Under the length of the block is meant the length of the front of work per excavator, which provides independent and productive operation of mining transportation equipment. The length of the block is determined by the conditions of rational technology of adjacent tsroizvodstvennyh processes - loosening, loading and transportation - in accordance with the “Standard projects of development systems and transportation at quarries." When designing the length of the block is taken according to practice, norms or standard projects ...

Tikhvin bauxite deposits, on the example of which are considered dependencies in the development of the front of work at open pits, dangerous for landslides, are characterized by an irregular shape, a small width (an average of 200-300 m) and a significant length (0.5-3 km). Due to the small thickness of deposits, mining works are carried out by one ledge, sometimes with division into sublevels, using upper and lower loading by excavators with buckets of 1-4 m3. The thickness of covering rocks is characterized by layered structure, change of lithological composition in transverse and longitudinal directions, fall of clay layers in some areas towards the mined-out space of the quarries, as well as watering of gravelly pebble deposits, sands, fractured limestone and bauxite rocks.

Already at the first stage of design there is a need to determine the volume of total and annual transportation of ore, rock and the upper contour of the open pit. From the volume of work for the design year, the capacity of the open pit Ap for ore is known in advance and the volume of rock work Bp is unknown, which must be determined for all subsequent calculations. Design calculations on the annual volume of rock works can be represented by the following dependencies.