NUMERCIAL MODELING OF THE STRESS-STRAIN STATE OF THE KURZHUNKUL OPEN-PIT MINE

The article discusses the possibilities of applying modeling of the stress-strain state of slopes to predict landslide hazard, which is very important for the successful implementation of all subsequent stages of design, construction and operation of engineering structures. The article considers the exist-ing approaches and methods used in the process of solving the problem, and determines the study as the type of mathematical modeling of the stress-strain state of a landslide body by the finite element method. It is shown that the selection of specific mathematical expressions for all subsequent calcula-tions is carried out depending on the specific type of landslide. The mechanisms of deformation and destruction of the slope under the action of gravitational forces are shown using the data of geodetic observations and engineering-geological surveys. As a result of the studies performed, calculations were made on several models illustrating the behavior of the soil massif of a landslide-prone slope. Stress patterns were obtained for a simple slope with a steepness of 35°, which coincide with the pre-viously published data of the physical experiment for the real open pit slope.

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Ensuring Wall Stability in the Course of Blasting at Open Pits of Kyzyl Kum Region

Mining science and technology ◽

10.17073/2500-0632-2020-3-235-252 ◽

2020 ◽

Vol 5 (3) ◽

pp. 235-252

Author(s):

Sh. Sh. Zairov ◽

Sh. R. Urinov ◽

R. U. Nomdorov

Keyword(s):

Rock Mass ◽

Strain State ◽

Boundary Integral Equations ◽

Video Recording ◽

Splitting Method ◽

Boundary Integral ◽

Open Pit ◽

Open Pit Mining ◽

Stress Strain ◽

Stress Strain State

Involvement of deep deposits in mining predetermined the trend of development of open pit mining towards increasing the depth of open pits. The main limitation imposed on drilling and blasting in the near-contour zone of an open pit is the need to protect the pit walls and engineering structures on the walls from seismic effects of huge blasts. As practice shows, the most effective and proven method of protecting pit walls is the use of blasting by presplitting method, creation of a shielding gap and a shielding layer of blasted rock mass, i.e. pre-splitting of the pit walls, preceding the huge blast. Therefore, the study of stress-strain state of the near-contour rock mass, determination of the parameters of blastholes for edge pre-splitting (preliminary shielding gap formation) in open pits is an urgent task. The analysis of the pit wall design and stress-strain state of rock mass at Kokpatas deposit exploited by Navoi Mining and Metallurgical Combine allowed to determine the model, as well as the method for calculating stress-strain state of the rock mass. When assessing stability of the pit walls, an approach known as the displacement method was used. Applying the boundary integral equations method allowed to develop an algorithm for calculating stresses in the rock mass for the conditions of Kokpatas deposit. A technique has been developed for experimental studies of blasting contour blasthole charges (blasting by pre-splitting method) using models, allowing to study fracturing on volumetric models and wave interaction by the method of high-speed video recording of the blasting process in transparent models, as well as to determine the parameters of stress waves during blasting in samples of real rocks. A method for formation of stable pit wall slopes, an excavator method for bench pre-splitting on ultimate envelope (contour) of a pit, and a method for initiating blasthole charges in the near contour zone of a pit have been developed and implemented in the industry.

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GEOMECHANICAL MODELING IN MINING AT THE ELGINSKY DEPOSIT

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2020-2-117-128 ◽

2020 ◽

Vol 2 ◽

pp. 117-128

Author(s):

Natalya A. Nemova ◽

Vladimir L. Gavrilov

Keyword(s):

Mechanical Properties ◽

Numerical Simulation ◽

Rock Mass ◽

Strain State ◽

Open Pit ◽

Coal Deposit ◽

Digital Models ◽

Stress Strain ◽

General Stress ◽

Stress Strain State

Using the Elginsky coal deposit as an example, the relevance of building digital models of geological objects to control the geomechanical condition of open-pit walls is shown. Physico-mechanical properties of overburden rocks are given. The results of numerical simulation of stress-strain state of the rock mass are presented. The directions of general stress displacements and zones of maximum displacements of the open-pit wall are determined and the maps of their distribution are compiled. It is shown that lower benches are more susceptible to tension.

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RESEARCH OF INFLUENCE OF UNFINISHED CONSTRUCTION EXCAVATION ON STRESS-STRAIN STATE OF EXPLOITED BUILDING BEARING STRUCTURES

Building constructions. Theory and Practice ◽

10.32347/2522-4182.2.2018.3-12 ◽

2018 ◽

Vol 0 (2) ◽

pp. 3-12

Author(s):

A Banakh

Keyword(s):

Strain State ◽

Stress Strain ◽

Stress Strain State

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КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ ОСОБЛИВОСТІ ХВОСТО-ВИХ БАЛОК СІТЧАСТОГО ТИПУ З ПОЛІМЕРНИХ КОМПО-ЗИЦІЙНИХ МАТЕРІАЛІВ ВЕРТОЛЬОТІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ

Open Information and Computer Integrated Technologies ◽

10.32620/oikit.2020.88.02 ◽

2020 ◽

pp. 15-30

Author(s):

А. Г. Гребеников ◽

И. В. Малков ◽

В. А. Урбанович ◽

Н. И. Москаленко ◽

Д. С. Колодийчик

Keyword(s):

Finite Element ◽

Strain State ◽

Layer Structure ◽

Metal Structure ◽

Element Model ◽

Stress Strain ◽

Element Analysis ◽

Mesh Structure ◽

Stress Strain State ◽

Mesh Structures

The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.

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