No 1 (2013)

The problem of plastic deformation of circular plate with hinged support fixed under action of impact loading in view of physical and geometrical nonlinearities is considered. Systems of the resolving equations are received, the algorithm and the program of numerical realization of a problem on the basis of a method of final differences is developed

A problem of interactions of structure with ground by boundary integral approach is solved in present article

Petrozavodskiy Gosudarstvenniy Universitet, Petrozavodsk We consider the calculation of the spatial component of inelastic rods of variable cross section along the length of the variable stiffness of the shear ties. The basis of the decision is an overall theory of elastic composite rods of A.R. Rzhanitsyn operating the space. An expres- sion for determining compliance with the shutters-rods under torsion takes into account the in- elastic work of branches and structural connections to the length of the rod panel.

In the scope of the paper, there were carried out calculations of highest possible load and probability of fail-safe functioning of thin sheet rolled-on profiles vault. The actuality of the research is caused by comprehensive study' insufficiency of thin sheet rolled-on U-form profiles vault's functioning reliability. The theoretical and methodological bases of the research are the theories of highest normal tensions and maximum strained conditions as well. In the course of the probability of the construction strength's failure's research there were applied modern software tools' means as Lira and SolidWorks. The results are the values of the highest possible thin sheet rolled-on profiles vault with reduced geometry features load and initial construction reliability. Results earned enabled to make a conclusion of insufficient vault's reliability.

Consideration is given to natural flexural vibrations in a stepwise cantilever beam with an attached distributed mass. The research shows that an increase in the initial coordinate of the distributed mass results in greater natural vibration frequencies within the parameter range in question. It has been found that as the ratio of the moments of inertia becomes greater, the first natural vibration frequency increases and the second and third ones decrease. The solu- tion of an inverse problem allows one to determine the initial coordinate, the magnitude of the attached distributed mass and also the ratio of the moments of inertia using three lowermost natural frequencies of flexural vibrations

Definition of the real physical and mechanical characteristics for the bedrock foundations of the hydraulic structures appears to be a crucial task. It begins to be a problem number one if the construction period is prolonged and causes deterioration of the foundation. The method of definition is suggested as clarification of the physical and mechanical characteristics for the bedrock foundations of the hydraulic structures on the basis of the numerical (finite element) modeling of the "structure-foundation" system strain-stress state, taking into account the field data studies which were made during specific construction phases. The data on the Boguchany HPP concrete dam are presented as the results of the calculated clarification of the physical and mechanical characteristics for the bedrock foundations.

The technique of constructing the impulse response function for the problems of identifi- cation of dynamic parameters of the structures on the example of building stadiums for the ski is presented. The results of theoretical and experimental researches are given. A comparison of methods is shown also.