Vlastislav Salajka

Assess of the Nuclear Power Plant Structures Residual Life and Earthquake Resistance

The paper deals with the seismic analysis of safety related structures of an operating nuclear power plant. At present time the nuclear power plants of VVER-400/213 type operate for over thirty years and there are arising requirements to verify the actual state of structures in order to assess their residual life in general. A sophisticated computation model has been developed for the seismic structural analysis using the ANSYS program package. The model involves the complex of all constrained structures of two main production blocks with equipment. In order to get a general view at the seismic load effects, seismic response analysis has been performed using direct integration of equations of motion in 25 sec interval at 0.01 sec step with excitation described by accelerograms. Combinations of dead loads and seismic loads have been considered in the stress assessment of the structures. The results of the performed analyses form a base for residual life prediction of selected structures

Calculation of Timber Outlook Tower with Influence of Behavior of “Steel-Timber” Connection

The paper describes the dynamics analysis of the timber truss tower structure located near Bohdaneč village. Regular static analysis and response on dynamic wind action detailed calculations of tower was performed. Article contents description of elaborated analysis, results summary and qualifying reliability of the structure considering dynamic wind effect in direction of the flow, vortex excitation and pedestrians’ movement action.

Response of Water Tower on Wind Induced Vibration Considering Interaction of Fluid and Structure

The paper deals with the numerical analysis of forced vibrations of a slender water tower structure. The computation model has been developed using finite elements in the ANSYS program environment. For CFD (Computational Fluid Dynamics) analysis the CFX module was used. The computation model includes the precisely modeled thin-walled steel structure and two variants of fluid domain. Elements FLUID30 formulated for direct description of the fluid pressure field has been applied and Lagrange description FLUID80. The Raleigh’s model of energy dissipation has been used. Similarity of normal modes of vibration has been applied as the criterion for defining the relations between computed natural frequencies of the empty tank and filled with water. To obtain accurate wind induced forces the CFD model of air surrounding was modeled. From this model the relation between velocity of unaffected stream and vortex separation frequency. Forced vibrations of the tower excited by vortex shedding harmonic pulsations have been computed.

Numerical simulations of tests masonry walls from ceramic block using a detailed finite element model

This article deals with an analysis of the behaviour of brick ceramic walls. The behaviour of the walls was analysed experimentally in order to obtain their bearing capacity under static loading and their seismic resistance. Simultaneously, numerical simulations of the experiments were carried out in order to obtain additional information on the behaviour of masonry walls made of ceramic blocks. The results of the geometrically and materially nonlinear computations were compared to the results of the performed tests.