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In order to determine a realistic behavior of the structure during earthquake action it is necessary to apply realistic load conditions and real parameters of structure characteristics. That can be fully accomplished only by testing the structure in full scale, as proscribed by the Regulations of technical standards for construction of high-rise structures in seismic areas, that is, experimental determination of dynamic characteristics is performed on the finished structure by forced vibrations which will not cause damage. Such tests produce quite satisfactory results in the field of elastic behavior of materials and structures, which is presumed during the earthquake action, i.e., the structure must not collapse. In the paper is described experimental research of a five-storey building constructed in a large panel prefabricated system taking into consideration the parameters of interaction of soil and structure. On the basis of obtained parameters, and by testing the structure in longitudinal and transversal directions and rotation, mathematical model of the tested structure is formed, and through analytical procedure the expected, i.e. measured values are calculated. The relation force-displacement will be given for the linear model of the system foundation-soil, and then will be given the equations of free vibrations in the matrix form, on whose basis a computer program was mode. [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]