scholarly journals Stress-strain state of spherical shells with two unequal holes

2021 ◽  
Vol 258 ◽  
pp. 09085
Author(s):  
Nurilla Noraliev ◽  
Bakhrom Ishniyazov ◽  
Bunyod Safarov ◽  
Oybek Saparov
Keyword(s):  
Finite Element Method ◽  
Composite Materials ◽  
Stress Concentration ◽  
Software Package ◽  
Shell Thickness ◽  
Strain State ◽  
Numerical Study ◽  
Shear Stiffness ◽  
The Finite Element Method ◽  
Spherical Shells

This article presents the results of a numerical study of the stress concentration around two equal and unequal holes in an orthotropic spherical shell made of composite materials under the action of internal pressure. The influence of geometric (hole radii, shell thickness, distance between holes) characteristics, as well as material orthotropy and shear stiffness, on the stress state of spherical shells made of composite materials is studied. A numerical algorithm based on the finite element method has been developed and a software package has been implemented on a computer that allows solving the problem of stress concentration near two unequal holes in spherical shells made of composite materials.

scholarly journals Vibrations of a deformed half-space with inclusion under the influence of surface waves

2021 ◽  
Vol 274 ◽  
pp. 03027
Author(s):  
Bakhodir Rakhmonov ◽  
Ismoil Safarov ◽  
Mukhsin Teshaev ◽  
Ravshan Nafasov
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Stress Concentration ◽  
Surface Waves ◽  
Strain State ◽  
Maximum Stress ◽  
Harmonic Waves ◽  
The Finite Element Method ◽  
Seismic Impacts ◽  
Good Agreement

There is a large number of underground tunnels of various shapes located in seismic zones that need to be protected from seismic impacts. The paper considers the effect of harmonic surface waves on a cylindrical inclusion of various shapes located in a viscoelastic half-plane. The main purpose of the study is to determine the stress-strain state of the obstacle when exposed to harmonic waves. The problem is solved by the finite element method. It was found that the maximum stress concentration is allowed at long waves, and the stress concentration with increasing depth and wavelength approaches the static value of stress. The reliability of the obtained research results is confirmed by good agreement with theoretical and experimental results obtained by other authors.

Reinforcement of Structures with Composite Materials

2019 ◽  
Vol 974 ◽  
pp. 535-541
Author(s):  
Galina M. Kravchenko ◽  
Elena V. Trufanova ◽  
Artem S. Osadchiy ◽  
Alina Sazonova
Keyword(s):  
Mechanical Properties ◽  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Composite Materials ◽  
Dynamic Characteristics ◽  
Strain State ◽  
Physical And Mechanical Properties ◽  
The Finite Element Method ◽  
New Materials

The aim of the work is to study the ways to strengthen the elements of the parametric architecture object framework based on the use of the new materials. The problem of strengthening the elements of the building frame is particularly relevant in connection with the development of the parametric architecture. Unlike the traditional methods of regulation and amplification, composite materials allow to change the stress-strain state and improve the dynamic characteristics of the parametric architecture object without increasing its own structures weight. The studies were performed using numerical simulation by the finite element method. Recommendations are given on the use of the physical and mechanical properties of the composite materials when strengthening the building framework.

scholarly journals Modeling the behavior of pedestrian railings taking into account their joint work with the span of bridges

2020 ◽  
Vol 7 (2) ◽  
Author(s):  
Vitaliy Koptilov ◽  
Vasiliy Lebedev ◽  
Boris Mandrik – Kotov ◽  
Ilya Ovchinnikov
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Composite Materials ◽  
Polymer Composite ◽  
Static Loading ◽  
Strain State ◽  
Polymer Composite Materials ◽  
The Finite Element Method ◽  
Joint Work ◽  
Bridge Structures

The problem of calculating pedestrian railing made of polymer composite materials on bridge structures is analyzed. It is noted that, although methods for calculating various products and structures made of polymer composite materials have been sufficiently developed, however, methods for calculating pedestrian railing are still just beginning to be developed. Normative methods for calculating pedestrian railing are very primitive and do not take into account all the features of their work. The article discusses the application of the finite element method to the calculation of pedestrian railing, and in addition to standard loads, the effect of the wind load and the joint work of the pedestrian railing with the span are taken into account. It is shown that the joint work of the pedestrian railing with the span, even under static loading, has a significant effect on its stress-strain state, increasing it, which in certain cases, in the presence of installation defects, leads to the destruction of the pedestrian railing from polymer composite materials.

Research of throwing areols of underground pipeline in permafrost

2021 ◽  
pp. 21-30
Author(s):  
T. S. Sultanmagomedov ◽  
◽  
R. N. Bakhtizin ◽  
S. M. Sultanmagomedov ◽  
T. M. Halikov ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Experimental Study ◽  
Finite Element ◽  
Strain State ◽  
Operating Temperature ◽  
Operating Conditions ◽  
Loss Of Stability ◽  
Underground Pipeline ◽  
The Finite Element Method ◽  
Permafrost Thawing

Study is due to the possibility of loss of stability of the pipeline in the process of pumping a product with a positive operating temperature and the formation of thawing halos. The article presents the ways of solving the thermomechanical problem of pipeline displacement due to thawing. The rate of formation of a thawing halo is investigated depending on the initial temperatures of the soil and the pumped product. The developed monitoring system makes it possible to study the rate of occurrence of thawing halos in the process of pumping the product. An experimental study on the formation of thawing halos around the pipeline was carried out on an experimental model. A thermophysical comparative calculation of temperatures around the pipeline on a model by the finite element method has been carried out. Keywords: underground pipeline; permafrost; thawing halo; monitoring; operating conditions; stress–strain state.

scholarly journals Modeling of Size Effects in Bending of Perforated Cosserat Plates

2017 ◽  
Vol 2017 ◽  
pp. 1-19 ◽  
Author(s):  
Roman Kvasov ◽  
Lev Steinberg
Keyword(s):  
Finite Element ◽  
Stress Concentration ◽  
Numerical Study ◽  
The Finite Element Method ◽  
Classical Elasticity ◽  
Element Analysis ◽  
Plate Deformation ◽  
The Finite Element Analysis ◽  
Circular Holes ◽  
Different Shapes

This paper presents the numerical study of Cosserat elastic plate deformation based on the parametric theory of Cosserat plates, recently developed by the authors. The numerical results are obtained using the Finite Element Method used to solve the parametric system of 9 kinematic equations. We discuss the existence and uniqueness of the weak solution and the convergence of the proposed FEM. The Finite Element analysis of clamped Cosserat plates of different shapes under different loads is provided. We present the numerical validation of the proposed FEM by estimating the order of convergence, when comparing the main kinematic variables with an analytical solution. We also consider the numerical analysis of plates with circular holes. We show that the stress concentration factor around the hole is less than the classical value, and smaller holes exhibit less stress concentration as would be expected on the basis of the classical elasticity.

scholarly journals Choice of technologies of ensuring exploitation suitability of buildings in the underground construction area

Vestnik MGSU ◽  
2020 ◽  
pp. 452-461
Author(s):  
Emil Imran Оglu Alirzaev ◽  
Marina E. Dement'eva
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Strain State ◽  
The Finite Element Method ◽  
Underground Construction ◽  
Underground Structures ◽  
Stress Strain ◽  
Computer Complex ◽  
Stress Strain State ◽  
Element Method

Introduction. One of the serious problems in the construction of underground structures in a dense urban area is the occurrence of excess deformations of the foundations of operating buildings that fall into the zone of influence of underground construction. The subject of the study was the calculated justification of the modern technology of compensatory injection. The relevance of the task is determined by the fact that the choice of the most effective protection technology should be based not only on a comparison of technological precipitation with maximum permissible values, but also on the assessment of the possibility of monitoring and controlling the movements of the foundations of buildings and structures during construction and subsequent operation. The purpose of the study was to compare various methods of protecting the foundations of existing buildings and structures and justify the selection of the most effective of them for further implementation and dissemination in the design and construction of urban underground structures. Materials and methods. On the basis of the survey data of the operated building falling into the impact zone of excavation of the pit for the construction of the installation and shield chamber of the subway, the parameters of the stress-strain state of its foundations are studied by mathematical modeling. The problem was solved by the finite element method based on the software and computer complex Z_Soil v.18.24. Results. Based on the analysis of the results of the examination of the administrative building using the finite element method, a change in the parameters of the stress-strain state of the foundations was modeled with various technologies for strengthening it. In the course of solving the geotechnical problem, it was found that the minimum impact on the foundations of the building during the construction of the pit was obtained in the method of compensatory injection. The system of criteria for making a decision on choosing an effective way to ensure the suitability of buildings in the underground construction zone for operation is substantiated. Conclusions. The results of this work can be used to justify the choice of technology for prevention and control of excess deformations of foundations. The function for calculating the volume of injected material in the Z_Soil software and computer complex can be used to justify the consumption of materials and the economic efficiency of the technological solution.

Numerical Modelling of Historic Vaulted Timber Structures

2013 ◽  
Vol 778 ◽  
pp. 517-525 ◽  
Author(s):  
Carina Fonseca Ferreira ◽  
Dina D’Ayala ◽  
Jose L. Fernandez Cabo ◽  
Rafael Díez
Keyword(s):  
Finite Element Method ◽  
Software Package ◽  
Structural Response ◽  
Shear Stiffness ◽  
Timber Structure ◽  
Structural Performance ◽  
Timber Structures ◽  
Global Response ◽  
Historic Structures ◽  
Numerical Approaches

Historic timber structures forming vaulted roofs of public and ecclesiastical buildings are present worldwide. The structural response of these constructions is usually governed by the structural performance of the joints, the interaction between the timber structure and the masonry parts, and the current condition of both joints and timber members. At present, numerical approaches, such as finite element method-based approaches are well-established tools for investigating the global response of complex historic structures. Using a FE-based software package, the authors developed a numerical model of a portion of an existing historic vaulted timber structure, which is part of the roof of the Cathedral of Ica in Peru, considering the in-plane semi-rigid response of the planked arches in the elastic range. For this purpose, the rotational and shear stiffness of the joints and the properties of the materials, which are assumed in good conditions, are calibrated by comparing the numerical outputs with experimental results available in literature. The aim of the work presented here is to compare the response of the same vault assuming either continuous (planks continuously connected) or discontinuous arches (modelling of the semi-rigid response of the joints which connect the planks together).

Sign in / Sign up

Export Citation Format

Share Document