Rock splitting, crack formation and propagation
Abstract
Energy costs have become one of the determining cost elements. The analysis of all high-energy production processes and the optimization of the process are of utmost importance and are essential for ensuring the competitiveness of a company. Rocks, and in a broader sense all soil and rock demolition, are energy-intensive processes. Two interconnected physical phenomena occur in this work process, the wear of the demolition tool and/or machine and the energy consumption associated with the construction of the demolition tools, the drive and energy supply and the supporting structure. Energy consumption is understood as the total energy requirement generated by the demolition tools in the production phase, the energy requirement of rock demolition plays a special role.
In this paper, I will give an energetic description of the cleavage process, which was partly done in [1] and [2], except that the formation and propagation of the crack were not clarified, which I will fill in here. The description of rock breaking according to [2] is fundamentally wrong because it models the cleavage with an approximate function. In these quasi-static rock cleavage models, the finite time requirement for crack propagation does not appear, the process takes place in approximately zero time.
The dynamic description of the physical process is beyond the scope of this article. This paper aims to fill the gap that I have addressed in Chapter 3 of [1], which is the description of crack initiation and crack propagation.
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