APPLICABILITY OF FINITE ELEMENT METHOD TO STRESS-STRAIN ANALYSIS OF NOTCHED STEEL PLATES AND CRITERION FOR DUCTILE CRACK INITIATOIN : Stress-strain states at steel connections Part 2

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.

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Experimental strain analysis of the high pressure strain gauge pressure transducer and verification by using a finite element method

Measurement Science and Technology ◽

10.1088/0957-0233/12/3/313 ◽

2001 ◽

Vol 12 (3) ◽

pp. 335-344 ◽

Cited By ~ 5

Author(s):

M H Orhan ◽

Ç Dogan ◽

H Kocabas ◽

G Tepehan

Keyword(s):

Finite Element Method ◽

Finite Element ◽

High Pressure ◽

Strain Gauge ◽

Pressure Transducer ◽

Strain Analysis ◽

Gauge Pressure ◽

Experimental Strain ◽

Element Method

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Application of finite element method (FEM) to study stress-strain state and distribution of temperatures in cutting zone in turning of various structural materials by carbide tools with coatings of various composition and architecture

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/613/1/012019 ◽

2019 ◽

Vol 613 ◽

pp. 012019 ◽

Cited By ~ 2

Author(s):

Alexey Vereschaka ◽

Boris Mokritskii ◽

Elena Mokritskaya ◽

Oleg Sharipov ◽

Catherine Sotova

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Strain State ◽

Structural Materials ◽

Stress Strain ◽

Stress Strain State ◽

Cutting Zone ◽

Element Method

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Nonhomogeneous Ventricular Wall Strain: Analysis of Errors and Accuracy

Journal of Biomechanical Engineering ◽

10.1115/1.2895530 ◽

1993 ◽

Vol 115 (4B) ◽

pp. 497-502 ◽

Cited By ~ 9

Author(s):

Lewis K. Waldman ◽

Andrew D. McCulloch

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Measurement Errors ◽

Three Dimensional ◽

Strain Analysis ◽

Noninvasive Methods ◽

Single Plane ◽

Cardiac Deformation ◽

Cardiac Strain ◽

Element Method

Nonhomogeneous distributions of strains are simulated and utilized to determine two potential errors in the measurement of cardiac strains. First, the error associated with the use of single-plane imaging of myocardial markers is examined. We found that this error ranges from small to large values depending on the assumed variation in stretch. If variations in stretch are not accompanied by substantial regional changes in ventricular radius, the associated error tends to be quite small. However, if the nonuniform stretch field is a result of substantial variations in local curvature from their reference values, large errors in stretch and strain occur. For canine hearts with circumferential radii of 2 to 4 cm, these errors in stretch may be as great as 30 percent or more. Moreover, gradients in stretch may be over- or underestimated by as much as 100 percent. In the second part of this analysis, the influence of random measurement errors in the coordinate positions of markers on strains computed from them is studied. Arrays of markers covering about 16 cm2 of ventricular epicardium are assumed and nonuniform stretches imposed. The reference and deformed positions of the markers are perturbed with Gaussian noise with a standard deviation of 0.1 mm, and then strains are computed using either homogeneous strain theory or a nonhomogeneous finite element method. For the strain distributions prescribed, it is found that the finite element method reduces the error resulting from noise by about 50 percent over most of the region. Accurate measurements of cardiac strain distributions are needed for correlation with and validation of realistic three-dimensional stress analyses of the heart. Moreover, with the advent of increasingly effective noninvasive methods to measure cardiac deformation such as magnetic resonance imaging, the use of nonhomogeneous strain analysis to determine more accurate strain distributions has increasing clinical significance.

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