Strength of earth dams considering the elastic-plastic properties of soils

The paper provides a detailed analysis of the current state of the problem. A mathematical model is presented to determine the dynamic behavior of earth dams, considering the viscoelastic properties of soil, using the hereditary Boltzmann-Volterra theory with the A.R. Rzhanitsyn kernel under periodic kinematic impacts. To solve the problems considered, the finite element method and complex arithmetics were used to reduce integrodifferential equations to a high-order complex algebraic equation. The accuracy of the methods was verified by solving test problems. Steadystate forced vibrations of the Pskem earth dam 195 m high are studied considering the real geometry and soil properties under resonant vibration modes. It was stated that the largest stress amplitudes in the body of the dam occur not only under the first resonance, but they can occur under other dense spectra of the eigenfrequencies of the dam, due to the interaction between close natural modes of vibration. The strength of various sections of the dam body was tested under kinematic impact using the Coulomb- Mohr theory of strength; the most dangerous sections of the dam were identified in terms of the highest stress.

Section: Introductionmentioning

confidence: 99%

Dynamic behavior of earth dams under different kinematic impacts

Mirsaidov

Toshmatov²

2023

“…In [19,20], a detailed review of known publications devoted to the study of the stress state and dynamic behavior of earth dams is presented, taking into account the elastic and elastoplastic properties of soil. A mathematical model was developed using the principle of virtual displacements to assess the stress-strain state of earth dams, considering the elasticplastic properties of soil under static loads.…”

Section: Introductionmentioning

confidence: 99%

Propagation of longitudinal waves in a linear viscoelastic medium

Khamidov,

Loginov,

Akbarov

2023

The article is devoted to the study of longitudinal wave propagation in a viscoelastic medium. A mathematical model of the problem of a linear viscoelastic medium was developed. The solution to the considered problems is reduced to the solution of a system of differential equations solved by the method of characteristics with the appropriate boundary conditions. The results are compared with known results obtained by other authors; a comparison shows the adequacy of the task posed. It was determined that the maximum values of stress, strain, and velocity of particles in viscous media vary according to a non-linear law. In the initial section of the medium and near it, first, the stress reaches its maximum, and then the strain and velocity of particles reach their maximum values.

“…The use of viscoelastic materials for the production of damping elements and the mathematical models used for their calculation are described. The simulation results showed that using dynamic dampers could significantly reduce the vibration amplitude of the building and increase its stability under conditions of strong external impacts, such as earthquakes [25].…”

Section: Introductionmentioning

confidence: 99%

Investigation of nonlinear oscillations of high rise flue gas stacks under various kinematic effects

Ishmatov,

Yuldoshev,

Khazratkulov

et al. 2023

A detailed analysis of the current state of the problem is presented in the article. A mathematical model is given to assess the dynamic behavior of high-rise structures, considering geometric nonlinearity (nonlinear dependence of strains on displacements) under periodic kinematic effects and the own weight of the structure. The unsteady forced oscillations of the high-rise flue gas stack of the Novo-Angrenskaya HPP were studied considering the geometric dimensions of the stack and the physical and mechanical characteristics of the material of the structure. The influence of dissipation in the material, leading to rapid or gradual damping of vibrations depending on the frequency spectrum of natural vibrations in one direction or another, as well as geometric nonlinearity, leading to an increase in the amplitude of vibrations at a low energy dissipation in the structure, and resonant impact, causing significant displacements of the structure. The predominant effect of energy dissipation in the material on the pattern of the dynamic behavior of a high-rise structure is observed compared to geometric nonlinearity.