Seismic stability estimation of designed NPP civil structures

This paper delas with seismic calculations of structures. Such calculations concern to area of dynamics of mechanical systems, but differ from calculations on other mechanical loads by basic impossibility of the exact specifying of perturbation action, as the seismic movement of a ground is a stochastic process, which concrete realization depends on many difficulty taken into account factors. Therefore the specific methods of the specifying of action and determination of sympathetic reaction of systems based on probabilistic reasons are used in seismic calculations. The seismic calculation of structure can be conditionally divided into four subproblems: 1)specifying of input data, including seismic; 2) determination of inertial seismic loads or caused by them displacements of structure; 3) computation of internal forces in structure, its supports, basis of a building etc. at a combination of seismic and other loads; 4) estimation of seismic resistance (strength, serviceability and etc.) of structure. Seismic design and calculations are based on achievements of many scientific disciplines: geophysics and engineering seismology, soil mechanics, mathematics, structural mechanics, dynamics of structures, hydrodynamics etc. The practical seismic calculations today are deterministic (nonprobabilistic) by form, though their methods are based on probabilistic preconditions