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Seismic effects that occur during mining in open pits are similar to the seismic effects of small and medium intensity earthquake. The paper outlines how the enormous energy is released during a strong earthquake and regardless of the hypocenter depth that could be dozens of kilometers, the area affected by a strong earthquake is very large and the intensity is very high. Notwithstanding the much lower energy released during mining, there is a seismic damage to buildings in the surroundings, as pits are usually near residential areas. A complex solution of the problems of mining and seismic effects can be reached only by experimental investigation. Earthquake can not be controlled, but the mining can be directed in full, especially by adequate amount of explosive charge and direction of mining. So this fact must be taken into account and proposed formulas are based on these conditions. A special note is given to the seismic anomaly that buildings closer to the field of mining are in some cases less affected than more distant ones. Therefore the new non-standard formulas will be given in the paper, which are more adequate for solving this seismic anomaly. The influence of blasting location with two boreholes charged, one with the initial explosive at the top and the second in the bottom of the drill, is analyzed. This approach significantly contributed to solving some anomalies, such as that much of the wave's energy is released in the area far away from the mine. Hence there is a need for better protection from seismic effects on buildings at these locations. [ABSTRACT FROM AUTHOR]

Efficient protection and construction of engineering and other structures in seismically active areas is a series of contradictions, where an optimum solution must be found, which does not comprise a compromise at the expense of safety and security of the people, and which minimizes damage of property. Along with the increase of the needs for energy, the need for open pit mining production increases, which is related to the mass blasting with increasing quantities of explosive, and nearing to the population centers. The seismic effects of blasting become more common, and also the seismic danger for the structures by mass blasting. The velocity of soil vibration during blasting depends on the quantity of explosive charge and distance of the blasting site and the affected structure. It is represented by equations containing a series of parameters including most of the relevant influences. These expressions are not uniform, because they depend on multiple influences, so it is most frequently necessary to experimentally determine them for each individual case. Therefore, seismic safety of structures during blasting is provided by a variety of factors with variable protection efficiency. [ABSTRACT FROM AUTHOR]